Patch: allows simple PIN to have a user-customizable number of decimal digits
Added option to enable key tap sound, as well as vibrate the device when unlock failed.
add vibrate feedback when passcode setup doesn't match
remove unlock sound since most people don't like it.
Merge pull request #30 from victorwon/master

Added option to enable key tap sound
Merge pull request #29 from EgoAleSum/patch_pinlength

Allows simple ping to have a user-customizable number of decimal digits