Added lgtv platform to control a LG Smart TV running NetCast 3.0 or 4.0 (#480)

* Added lgtv platform to control a LG Smart TV running NetCast 3.0
(LG Smart TV models released in 2012) and NetCast 4.0 (LG Smart TV models released in 2013).

* Update media_player.lgtv.markdown

* Rename media_player.lgtv.markdown to media_player.lg_netcast.markdown

source/_components/media_player.lg_netcast.markdown

@@ -0,0 +1,44 @@
+---
+layout: page
+title: "LG Netcast TV"
+description: "Instructions how to integrate a LG TV (Netcast 3.0 & 4.0) within Home Assistant."
+date: 2016-05-12 23:22
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: lg.png
+ha_category: Media Player
+ha_iot_class: "Local Poll"
+ha_release: 0.20
+----------------
+
+The `lg_netcast` platform allows you to control a LG Smart TV running NetCast 3.0
+(LG Smart TV models released in 2012) and NetCast 4.0 (LG Smart TV models released in 2013).
+For the new LG WebOS TV's use the [webostv](/components/mediaplayer.webostv) platform.
+
+To add a LG TV to your installation, add the following to your `configuration.yaml` file:
+
+```yaml
+# Example configuration.yaml entry
+media_player:
+  platform: lg_netcast
+  host: 192.168.0.20
+  access_token: 889955
+  name: Living Room TV
+```
+
+Configuration variables:
+
+- **host** *Required*: The IP of the LG Smart TV, e.g. 192.168.0.20
+- **access_token** *Optional*: The access token needed to connect.
+- **name** *Optional*: The name you would like to give to the LG Smart TV. The default is "LG TV Remote".
+
+To get the access token for your TV configure the `lg_netcast` platform in Home Assistant without the `access_token`.
+After starting Home Assistant the TV will display the access token on screen.
+Just add the token to your configuration and restart Home Assistant and the media player component for your LG TV will show up.
+
+<p class='note'>
+The access token will not change until you factory reset your TV.
+</p>
+