Fixed layout issue in add alarm activity

 - The add new alarm activity allows for scrolling on smaller
    screens or in landscape mode
Undo popup on alarm deletion

 - Added functionality to restore lastly deleted alarm
 - A popup appears when deleting an alarm, promting the user
    to undo the last action ( Source code from:
    https://code.google.com/p/romannurik-code/source/browse/misc/undobar
    )