release 2.1 (#447)

* [android] [auto] Update properties to version 2.1.0 in preparation for build.

* changed version to 2.2.0-snapshot

Author: Cameron Mace

mapbox/gradle.properties

@@ -1,5 +1,5 @@
 # Project-wide Gradle settings.
-VERSION_NAME=2.1.0-SNAPSHOT
+VERSION_NAME=2.2.0-SNAPSHOT
 GROUP=com.mapbox.mapboxsdk
 
 POM_URL=https://github.com/mapbox/mapbox-java