refactor PhysicsContact inherits from EventCustom; simplify emitting collision events
fix compile error
remove the workaround cast
Merge branch 'physics_event' of https://github.com/edwardzhou/cocos2d-x into iss3716_refactor_physicscontact

Conflicts:
	cocos/physics/CCPhysicsContact.h
issue #3716: refactor physics contact
closed #3716: edit lua support
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-x into iss3716_refactor_physicscontact
Merge commit 'refs/pull/5268/head' of git://github.com/cocos2d/cocos2d-x into merge5268

Conflicts:
	tests/test-javascript/tests
Compilation error fix after merging https://github.com/cocos2d/cocos2d-x/pull/5311
Merge pull request #5314 from dumganhar/develop

Compilation error fix after merging PR #5311
[AUTO] : updating submodule reference to latest autogenerated bindings
Merge pull request #5315 from CocosRobot/updategeneratedsubmodule_1392011921

[AUTO] : updating submodule reference to latest autogenerated bindings
Merge pull request #5256 from Dhilan007/develop_label

Label::reduce unnecessary calculation amount.
Merge branch 'develop' of git://github.com/cocos2d/cocos2d-x into merge5268
Merge pull request #5312 from dumganhar/merge5268

closed #3716:PhysicsContact should be inherited from EventCustom, it will simplify the logic of emitting collision events
move labelttf's platform-dependent code from CCImage to CCDevice