Initial commit of SimpleToDo
Initial commit
Made several changes: 
1)Added customized icons for res/drawable(mdpi,hdpi,xhdpi, and xxhdpi)
2)Changed color of text custom style
3)Added text validation for user input error on TodoActivity and
EditItemActivity:
	-user no longer able to save a blank to do item upon editing
	-Error message appears and gives specific error message.  
	-Error icon appears and alerts user to error
	-Error message disappears once user begins to type. This
functionality saves user from having to click away error message.(user
friendly)
Updated UI - moving edit text to the top of screen so as to not conflict
w/visibility while using keyboard. 
Added user info to explain basic functionality
Updated UI so that edit text entry doesn't interfere with keyboard.
Added user guide pop up.