Added mychevy docs (#4410)

* Added mychevy docs

* ✏️ Update ha_release

* ✏️ Removed configuration variables header

source/_components/mychevy.markdown

@@ -0,0 +1,73 @@
+---
+layout: page
+title: "MyChevy"
+description: "Instructions on how to integrate Chevy Bolt car into Home Assistant."
+date: 2017-08-28 17:00
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: chevy.png
+ha_category: Hub
+ha_release: 0.62
+ha_iot_class: "Cloud Polling"
+---
+
+The `MyChevy` component communicates with the
+[my.chevrolet](https://my.chevrolet.com) website using selenium to log
+in as your user, and screen scrape the data provided. GM does not
+make it easy to sign up for any official development program, so this
+provides a workaround to get access to your data.
+
+This component provides the following platforms:
+ - Binary sensors - if the car is plugged in
+ - Sensors - such as Battery Level, Charge Mode, EST Range, Total
+   Distance Traveled
+
+To use MyChevy in your installation, add the following to your `configuration.yaml` file:
+
+```yaml
+# Example configuration.yaml entry
+mychevy:
+  username: email
+  password: password
+```
+
+{% configuration %}
+username:
+    description: The email address associated with your my.chevrolet account
+    required: true
+    type: string
+password:
+    description: The password for your given my.chevrolet account
+    required: true
+    type: string
+{% endconfiguration %}
+
+
+#### {% linkable_title Installation %}
+
+Because this uses selenium behind the scenes, installation is more
+complicated than merely pip install. See the installation instructions
+at https://github.com/sdague/mychevy.
+
+#### {% linkable_title Limitations %}
+
+The architecture of the GM automotive networking imposes some
+limitations on the functionality of the component.
+
+The OnStar network link is very slow, and takes 1 - 3 minutes to get
+information back from the car. As such the mychevy component only
+polls every 30 minutes to not overwhelms that connection.
+
+The OnStar network (or more specifically the gateway used by the
+my.chevrolet website) appears to suffer more than most networks when
+the car is a) in a garage, and b) it's cold outside (like < 15 degrees
+F). One of the provided sensors is a status sensor which indicates if
+we got connectivity with the car on the last polling cycle or not.
+
+The "API" for this is written by web scraping. As such, it only
+currently is known to work if you have a Chevy Bolt EV, and only 1
+Chevy car connected to OnStar. Patches for extended support should go
+to the https://github.com/sdague/mychevy project first, then
+Home Assistant can be extended.