No ui-elements. Project can be built used as a jar file.

The idea of these changes is to allow the user to build a jar file from the BoxAndroidLibraryV2 with it's dependencies, which can be shrinked with proguard. This will make the project usable in large projects that are already close to the methods count limit.
As resources cannot be included in the jar file, the OAuthActivity creates a dynamic content (web)view and the other activities are removed.