Client: moved class files to components directory with use of Object.create
Client: added Position class and use it in board.getInitAvailPos and
board.getInhandAvailPos
Client: renamed board to game and moved Position.js file out of components dir
Client: added board singleton class with setAvailable method and use it from custom.js
Client: added resetAvailable method to board and use it from custom.js
Client: modified constructors of Position and Piece to take different kind of params
Client: Board and Piece holds its data
Client: main: refactored around setInitialPieces function