New icon for the sample app
Updated sample app, new clear all button, welcome text and link to github, fixed bug with fragment
Reverted change to AES/CBC/PKCS5Padding after finding issues on Android <4.0, refactored to use a backup PBE key Algorithm as some issues on older devices with PBKDF2WithHmacSHA1, new method to allow get/set unencrypted which is useful when the value is already encrypted.