updated chess.js
added Jasmine tests
added failed tests:
- Red to move first, not Black
- Red cannot make 2 moves consecutively
passed 2 previous failed tests
- added a turn_ flag to keep track of Red or Black turn
- set Red to move first
added failed tests for Bing piece
reformat code: put extra space after if/for to distict with function calls
passed all failed tests
- Bing now move correctly
- other pieces disabled for now