Initial commit of they simple keyboard state tracker for blog post part 1
Renamed use of custom EditText extension to match definition
PR Feedback:

*Lower minSdkVersion from 16 to 4
*Rename custom EditText to be more distinct
*Move strings to be XML constants
Style changes for demo gif and demo gif itself.
Add sample APK
Merge pull request #1 from twotoasters/ben-simple-keyboard-tracker

Initial commit of they simple keyboard state tracker for blog post part 1