Fix: typo "MainActitivy" to "MainActivity"
Add: cancel alarm implement
Add: a boot complete event receiver to restart alarm after boot
Add: Get information about whether could set lock screen wallpaper
Add: checkbox preference to update wallpaper or lockpaper
Add: A function that update wallpaper according to shared preference
Refresh wallpaper when destination date changed
Extract string resource, change app name to chinese.
Fix: remove test code, that set alarm every 5 seconds.
Modify Icon.
Merge branch 'dev'