Add Captive Portal (#624)

* WIP: Captive Portal

* Updates

* Updates

* Lint

* Fixes

esphome/components/web_server_base/__init__.py

@@ -0,0 +1,24 @@
+import esphome.config_validation as cv
+import esphome.codegen as cg
+from esphome.const import CONF_ID
+from esphome.core import coroutine_with_priority, CORE
+
+DEPENDENCIES = ['network']
+
+web_server_base_ns = cg.esphome_ns.namespace('web_server_base')
+WebServerBase = web_server_base_ns.class_('WebServerBase', cg.Component)
+
+CONF_WEB_SERVER_BASE_ID = 'web_server_base_id'
+CONFIG_SCHEMA = cv.Schema({
+    cv.GenerateID(): cv.declare_id(WebServerBase),
+})
+
+
+@coroutine_with_priority(65.0)
+def to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    yield cg.register_component(var, config)
+
+    if CORE.is_esp32:
+        cg.add_library('FS', None)
+    cg.add_library('ESP Async WebServer', '1.1.1')