Changed Dex Mojo so that it includes jars in the AR libs folder.

Changed Dex Mojo so that it adds in jars based upon the defined dependencies (including SYSTEM scope deps). This captures all the APKLIB and AAR libs folder jars as well as the AAR classes jars without requiring any special processing. This means that AAR libs folder actually get Dexed into the APK now.

I am a little concerned that removing SYSTEM scope from EXCLUDED_SCOPES might cause some other problem. I haven't run it against the samples yet. If someone could do that I would be much obliged.

Removed noisy log.