updated build.gradle
Merge branch 'xcore_2.0' of https://github.com/IstiN/android_xcore into xcore_2.0

Conflicts:
	xcore-library/plugin_ab_pull_to_refresh/build.gradle
	xcore-library/xcore/build.gradle
Merge branch 'xcore_2.0_dev' of https://github.com/IstiN/android_xcore into xcore_2.0