🏗 Merge C++ into python codebase (#504)

## Description:

Move esphome-core codebase into esphome (and a bunch of other refactors). See https://github.com/esphome/feature-requests/issues/97

Yes this is a shit ton of work and no there's no way to automate it :( But it will be worth it 👍

Progress:
- Core support (file copy etc): 80%
- Base Abstractions (light, switch): ~50%
- Integrations: ~10%
- Working? Yes, (but only with ported components).

Other refactors:
- Moves all codegen related stuff into a single class: `esphome.codegen` (imported as `cg`)
- Rework coroutine syntax
- Move from `component/platform.py` to `domain/component.py` structure as with HA
- Move all defaults out of C++ and into config validation.
- Remove `make_...` helpers from Application class. Reason: Merge conflicts with every single new integration.
- Pointer Variables are stored globally instead of locally in setup(). Reason: stack size limit.

Future work:
- Rework const.py - Move all `CONF_...` into a conf class (usage `conf.UPDATE_INTERVAL` vs `CONF_UPDATE_INTERVAL`). Reason: Less convoluted import block
- Enable loading from `custom_components` folder.

**Related issue (if applicable):** https://github.com/esphome/feature-requests/issues/97

**Pull request in [esphome-docs](https://github.com/esphome/esphome-docs) with documentation (if applicable):** esphome/esphome-docs#<esphome-docs PR number goes here>

## Checklist:
  - [ ] The code change is tested and works locally.
  - [ ] Tests have been added to verify that the new code works (under `tests/` folder).

If user exposed functionality or configuration variables are added/changed:
  - [ ] Documentation added/updated in [esphomedocs](https://github.com/OttoWinter/esphomedocs).

tests/test1.yaml

@@ -2,12 +2,6 @@ esphome:
   name: test1
   platform: ESP32
   board: nodemcu-32s
-  # Use this for testing while developing:
-  # Note the travis check for esphome PRs will fail until the
-  # esphome-core PR has been merged.
-  # esphome_core_version:
-  #   local: ~/path/to/esphome-core
-  use_custom_code: false
   on_boot:
     priority: 150.0
     then:
@@ -709,18 +703,6 @@ output:
   - platform: my9231
     id: my_5
     channel: 5
-  - platform: copy
-    id: my_copy1
-    outputs:
-      - my_1
-      - my_2
-      - my_3
-  - platform: copy
-    id: my_copy2
-    type: binary
-    outputs:
-      - id22
-      - id2
 
 light:
   - platform: binary
@@ -874,6 +856,7 @@ light:
 
 remote_transmitter:
   - pin: 32
+    carrier_duty_percent: 100%
 
 switch:
   - platform: gpio
@@ -883,92 +866,94 @@ switch:
     inverted: True
     command_topic: custom_command_topic
     restore_mode: ALWAYS_OFF
-  - platform: remote_transmitter
-    name: "JVC Off"
-    jvc:
-      data: 0x10EF
-    repeat: 25
-  - platform: remote_transmitter
-    name: "Panasonic TV Off"
-    nec:
-      address: 0x4242
-      command: 0x8484
-    repeat: 25
-  - platform: remote_transmitter
-    name: "Panasonic TV Off"
-    lg:
-      data: 4294967295
-      nbits: 28
-    repeat: 25
-  - platform: remote_transmitter
-    name: "Panasonic TV Off"
-    samsung:
-      data: 0xABCDEF
-    repeat: 25
-  - platform: remote_transmitter
-    name: "Panasonic TV Off"
-    sony:
-      data: 0xABCDEF
-      nbits: 12
-    repeat: 25
-  - platform: remote_transmitter
-    name: "Panasonic TV Off"
-    panasonic:
-      address: 0x4004
-      command: 0x1000BCD
-    repeat: 25
-  - platform: remote_transmitter
-    name: "Panasonic TV Off"
-    rc_switch_raw:
-      code: '001010011001111101011011'
-      protocol: 1
-    repeat: 25
-  - platform: remote_transmitter
-    name: "Panasonic TV Off"
-    rc_switch_type_a:
-      group: '11001'
-      device: '01000'
-      state: True
-      protocol:
-        pulse_length: 175
-        sync: [1, 31]
-        zero: [1, 3]
-        one: [3, 1]
-        inverted: False
-    repeat: 25
-  - platform: remote_transmitter
-    name: "Panasonic TV Off"
-    rc_switch_type_b:
-      address: 4
-      channel: 2
-      state: True
-  - platform: remote_transmitter
-    name: "Panasonic TV Off"
-    rc_switch_type_c:
-      family: 'a'
-      group: 1
-      device: 2
-      state: True
-  - platform: remote_transmitter
-    name: "Panasonic TV Off"
+  - platform: template
+    name: JVC Off
     id: living_room_lights_on
-    rc_switch_type_d:
-      group: 'a'
-      device: 2
-      state: True
-  - platform: remote_transmitter
-    name: "Panasonic TV Off"
-    rc5:
-      address: 0x00
-      command: 0x0B
-  - platform: remote_transmitter
-    name: "Panasonic TV Off"
+    turn_on_action:
+      remote_transmitter.transmit_jvc:
+        data: 0x10EF
+  - platform: template
+    name: NEC
     id: living_room_lights_off
-    raw:
-      carrier_frequency: 35kHz
-      data:
-      - 1000
-      - -1000
+    turn_on_action:
+      remote_transmitter.transmit_nec:
+        address: 0x4242
+        command: 0x8484
+  - platform: template
+    name: LG
+    turn_on_action:
+      remote_transmitter.transmit_lg:
+        data: 4294967295
+        nbits: 28
+  - platform: template
+    name: Samsung
+    turn_on_action:
+      remote_transmitter.transmit_samsung:
+        data: 0xABCDEF
+  - platform: template
+    name: Sony
+    turn_on_action:
+      remote_transmitter.transmit_sony:
+        data: 0xABCDEF
+        nbits: 12
+  - platform: template
+    name: Panasonic
+    turn_on_action:
+      remote_transmitter.transmit_panasonic:
+        address: 0x4004
+        command: 0x1000BCD
+  - platform: template
+    name: RC Switch Raw
+    turn_on_action:
+      remote_transmitter.transmit_rc_switch_raw:
+        code: '001010011001111101011011'
+        protocol: 1
+  - platform: template
+    name: RC Switch Type A
+    turn_on_action:
+      remote_transmitter.transmit_rc_switch_type_a:
+        group: '11001'
+        device: '01000'
+        state: True
+        protocol:
+          pulse_length: 175
+          sync: [1, 31]
+          zero: [1, 3]
+          one: [3, 1]
+          inverted: False
+  - platform: template
+    name: RC Switch Type B
+    turn_on_action:
+      remote_transmitter.transmit_rc_switch_type_b:
+        address: 4
+        channel: 2
+        state: True
+  - platform: template
+    name: RC Switch Type C
+    turn_on_action:
+      remote_transmitter.transmit_rc_switch_type_c:
+        family: 'a'
+        group: 1
+        device: 2
+        state: True
+  - platform: template
+    name: RC Switch Type D
+    turn_on_action:
+      remote_transmitter.transmit_rc_switch_type_d:
+        group: 'a'
+        device: 2
+        state: True
+  - platform: template
+    name: RC5
+    turn_on_action:
+      remote_transmitter.transmit_rc5:
+        address: 0x00
+        command: 0x0B
+  - platform: template
+    name: RC5
+    turn_on_action:
+      remote_transmitter.transmit_raw:
+        code: [1000, -1000]
   - platform: template
     name: Living Room Lights
     id: livingroom_lights
@@ -1061,8 +1046,8 @@ interval:
     then:
     - display.page.show: !lambda |-
         if (true) return id(page1); else return id(page2);
-    -  display.page.show_next: display
-    -  display.page.show_previous: display
+    -  display.page.show_next: display1
+    -  display.page.show_previous: display1
 
 display:
 - platform: lcd_gpio
@@ -1094,7 +1079,7 @@ display:
   model: "SSD1306 128x64"
   reset_pin: GPIO23
   address: 0x3C
-  id: display
+  id: display1
   pages:
     - id: page1
       lambda: |-