added joined request
Demo for multi request added
added some todo's
IDBHelper interface added
DBHelper performance optimization
added gitignore
Merge branch 'feature/joinRequest' of https://github.com/IstiN/android_xcore into arch/modelContentProvideOptimization

Conflicts:
	.gitignore
fix db creation issue
compile fixed
content provider refactoring started
DBHelper performance optimization
Merge branch 'arch/modelContentProvideOptimization' of https://github.com/IstiN/android_xcore into arch/modelContentProvideOptimization

Conflicts:
	.gitignore
contentprovider refactored, added sqlite support tests
add support batch operations
fix compiled
integration and loading/empty/second loading fixed
Added DB connection interface to make easy way to use external DB
compile errors fixed
abstraction is done
DB refactoring done