RxPermissions Versions Save

This release contains the migration to RxJava3, thanks to the work of @galuszkak with #326.

This release contains the migration to androidX, thanks to the work of @galuszkak with #325.

• #23 Add check for isPermissionRevokedByPolicy

• Don't ask the framework for already granted permissions.

• Fix bug in RxPermissions.shouldShowRequestPermissionRationale() : Don't call activity.shouldShowRequestPermissionRationale() for granted permissions.

• Fix #3
• shouldShowRequestPermissionRationale can take multiple permissions.

• shouldShowRequestPermissionRationale basic support #9
• Return a detailed permission report rather than just a boolean #5