Add button view component into MainActivity and a listener setting
statement.
Add an onClickListener implementation method.
Create gh-pages branch via GitHub
Merge remote-tracking branch 'origin/gh-pages' into add-slider
Merge branch 'add-button' into add-slider

Conflicts:
	eclipse-project/Lesson01/res/layout/activity_main.xml
	eclipse-project/Lesson01/src/com/dev_training/android/lesson01/MainActivity.java