[Component] Piece

**Basic:**
- [x] #12
- [x] #13
- [x] #14
- [x] #16
- [x] #18
- [x] #19
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**Different types of pieces**:
- [x] #17
- [x] #20
- [x] #22
- [x] #24
- [ ] #28
- [ ] #29
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**Solution**
- The Piece class must contain two properties defining the _position of the piece_ and the _alliance of the piece_.
- The `calculateLeagalMoves` method must return a collection of `Moves` and must be abstract as it will be different for different types of pieces.

Review the completed and unchecked checklist items in this issue to understand the existing piece types and remaining scope. Start from the Piece class and its calculateLeagalMoves entry point; done means Piece defines position and alliance and requires each piece type to provide its legal moves.

Written by the indexing model from the issue text.