Add move context for repertoire moves #7
Description
When receiving a move for training, optionally "play back" X number of moves for the user so he can see which moves led up to this one.
Provide an option in settings so the user can select how many moves he wants to have replayed before he trains a move
Also, provide an option to select the speed of the move replays (easy to implement w/ chessground's animation.duration)
Look at websites like chesstempo as an exaple