Add android-6-runtime-permission-check-mechanism support

[k3b]

Implement the new android-6-runtime-permission-check-mechanism as described https://developer.android.com/training/permissions/requesting.html and
https://material.google.com/patterns/permissions.html

Open Questions:

Is it possible in Android-6+ to ask for a permission (or permissoingroup) at runtime that is not declared in the manifest? If yes adding a uri at runtime should also allow to add permissions to be stored, too

Help wanted

At the moment "k3b" (the owner of this repository) has no android-6 device and therefore will not implement this ticket. Megerequests are welcome.

[ahsim]

still wait android 6+ support

[1ZIP]

Add plx

[k3b]

May be helpfull to implement this feature: https://github.com/afollestad/assent