Handling Android 6.0 permissions

I finally got around to handling the new Android 6.0 permissions properly.  A2DP Volume requires many permissions which are explained here: https://github.com/jroal/a2dpvolume/wiki/Permissions-Explanation.  Android 6 brings a new way to allow the users line item veto, at least to some degree which is explained here: https://developer.android.com/guide/topics/permissions/index.html.  If you are on A2DP Volume version 2.12.8 or older, and you first installed A2DP Volume on a device with Android 6 or higher then you may run into problems with features not working or even app crashing.  The temporary fix for this is to go to Android settings -> apps and select A2DP Volume.  Then click the "permissions" button and enable all permissions.  A2DP Volume 2.12.9 will fix this by explaining and requesting permissions when you first open the app.