Implements android gamecenter functions.

Add java code called through JNI.
GameHelper.java is provided by google with Apatch License V2.0.
Add include library.
Add provisional button on title scene for sign in/out
Load android achievement id from plist
Implement registration of leaderboard, achievement
Update app activity to use GameCenter
Add compile macro for only use on android method
Update for changing of compile config
Merge branch 'master' into android_gamecenter
Add achievement info on android game center
Divert resource strings
Fix code based review

change process of incremental achievement updating.
add loading all achievement data as initializing.
Revert title scene from debug status
turn off debug flg
Add call back to GameEngine when login state changed

follow up achievement state updating
Show alert dialog on android when tapped ranking/achievement button if user doesnt signed in
Change alert dialog message when user not loged in
Merge branch 'master' into android_gamecenter
Merge pull request #29 from ichiko/android_gamecenter

Android版ゲームセンター対応