Fixes and improvements to piece movement

Fixed piece movement so strings now translate into the correct
positions.
Added a check on addPiece to make sure we aren't trying to move on top
of one of our own units
Fixed bug that caused segfault when empty string entered as command.
Added check to movePiece using getMovable but seems to prevent all
movemenet so commented out for now.
Revert "Fixes and improvements to piece movement"

This reverts commit cbb83f196f29b7fbbc65a3278c916dcda7a6db00.
Fixes and improvement to piece movement

Fixed piece movement so strings now translate into the correct
positions.
Added a check on addPiece to make sure we aren't trying to move on top
of one of our own units.
Fixed bug that cuased sefault when empty string entered as command.
Added check to movePiece using getMovable but seems to prevent all
movement so commented out for now.