First commit of Android Tip Calculator.  Tip Calculator has all required
features and one optional feature.

Required: User is displayed the tip of specified percentage for
specified entered amount
Required: User enters the total amount of the transaction
Required: User can select between tip amounts (i.e 10%, 15%, 20%)
Required: Upon selecting tip amount, formatted tip value is displayed
Optional:  Improve the user interface and experience by using images
and/or colors