Draw a board using canvas and use AJAX requests to make moves and update the board state
Changed Rook and Knight

Changed the code for rook and knight, so that they are displayed at the
right position now. @svetakrasikova you have done a really good work. I
don't even try to imagine how much time that must have taken you.
inverted rank and file
Implement updating moves on the chess board; move show view
Clean moves_helper.rb
Fix typo in moves controller, add comments