timob-16180: implement snapshot.
Merge branch 'master' of https://github.com/appcelerator-modules/ti.map into timob-16180-3

Conflicts:
	android/src/ti/map/TiUIMapView.java
	android/src/ti/map/ViewProxy.java
timob-16180: Changed name, added docs + test cases.
timob-16180: change 'onsnapshotready' to event
timob-16180: fixed doc
timob-16180-3: addressed comments
Merge pull request #32 from hieupham007/timob-16180-3

Timob 16180 3: Add snapshot support