app.Uri2Path needs deprecating

[dhurren]

In recent versions of Android, its no longer to query the content database for the _data column (for security reasons) which makes it impossible to work out the original file path. So we need to mark app.Uri2Path as deprecated in the docs and make sure all DS methods can cope with URI as well as absolute path.

[alex-Symbroson]

fixed by 32b649c