Added tmp102 temperature sensor support (#929)

* Added tmp102 temperature sensor support

* Added sensor to test3.yaml

* Moved docstring to component root

* Tweak formatting from clang-format script

* Removed extra newline at the end of the file to satisfy pylint

* Update schema to match that of other single-value sensors

In ESPHome, sensors that only expose one value do not put the sensor under another key.

* Add missing import

* Fix test after structural change to component

* removed unused setting

* Update esphome/components/tmp102/tmp102.cpp

Co-authored-by: Otto Winter <otto@otto-winter.com>
Co-authored-by: Guillermo Ruffino <glm.net@gmail.com>
Co-authored-by: Jesse Hills <3060199+jesserockz@users.noreply.github.com>

esphome/components/tmp102/sensor.py

@@ -0,0 +1,30 @@
+"""
+The TMP102 is a two-wire, serial output temperature
+sensor available in a tiny SOT563 package. Requiring
+no external components, the TMP102 is capable of
+reading temperatures to a resolution of 0.0625°C.
+
+https://www.sparkfun.com/datasheets/Sensors/Temperature/tmp102.pdf
+
+"""
+import esphome.codegen as cg
+import esphome.config_validation as cv
+from esphome.components import i2c, sensor
+from esphome.const import CONF_ID, UNIT_CELSIUS, ICON_THERMOMETER
+
+DEPENDENCIES = ['i2c']
+
+tmp102_ns = cg.esphome_ns.namespace('tmp102')
+TMP102Component = tmp102_ns.class_("TMP102Component", cg.PollingComponent, i2c.I2CDevice,
+                                   sensor.Sensor)
+
+CONFIG_SCHEMA = sensor.sensor_schema(UNIT_CELSIUS, ICON_THERMOMETER, 1).extend({
+    cv.GenerateID(): cv.declare_id(TMP102Component),
+}).extend(cv.polling_component_schema("60s")).extend(i2c.i2c_device_schema(0x48))
+
+
+def to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    yield cg.register_component(var, config)
+    yield i2c.register_i2c_device(var, config)
+    yield sensor.register_sensor(var, config)