Add downloaded files to the media library.

Since we can't download the file directly to it's final destination, we can't
have the download manager requisting the file scanned by the media server.
Instead we do it in broadcast receiver which listens for completed downloads.
As it is not allowed to bind to a service from a broadcast receiver, we can't
call MediaScannerConnection.scanFile, because it internally binds to the
media service.
So we use the ACTION_MEDIA_SCANNER_SCAN_FILE intent action to have the file
scanned.

This fixes a comment on issue #55.

Signed-off-by: Kurt Aaholst <kaaholst@gmail.com>
Merge remote-tracking branch 'nik/develop' into develop
Add downloaded files to the media library.

Since we can't download the file directly to it's final destination, we
can't have the download manager request that the file be scanned by the
media server.

Instead we do it in broadcast receiver which listens for completed
downloads.

As it is not allowed to bind to a service from a broadcast receiver,
we can't call MediaScannerConnection.scanFile, because it internally
binds to the media service.

So we use the ACTION_MEDIA_SCANNER_SCAN_FILE intent action to have the
file scanned.

This fixes a comment on issue #55.
Use an explicit version of Gradle to ensure reproducibility.