feat: music player shuffle and repeat features

[balaji-ramavathu]

Fixes #493
Fixes #323

Changes made:

1. The shuffle option toggles between shuffle on and off, everytime the shuffle mode is changed, it is stored in shared preferences and if the shuffle mode is on, the audio files will be shuffled before going to the media source.
2. The repeat option toggles between repeat all and repeat one As repeat all is already implemented, repeat only current file is made by using LoopingMediaSource.

Screenshots

[chirag-jn]

Proposing PR #576 to fix merge issues.