All versions of QRSA OTP Authentication

1.4: - Added Md5 hash verification, to further protect against malleability attacks. 1.3: - Improved code so the app can more reliable kill itself. 1.2: - Added OTP into @string/app_name to match Google Play app name. 1.1: - Changed enroll function to exclude linebreaks in the public key. - Added new "u" enroll function. Read the description or GitHub page for more information. The "u" enroll function is recommended when enrolling from a computer.