fenGet() referenced values

[ajax333221]

We should kill all the references before returning the values to prevent unwanted behavior.

Currently, the board properties that are Object type (objects and arrays) that might be affected are:

• w
• b
• moveList
• legalUci
• legalUciTree
• legalRevTree
• squares

The temporal board where they come gets deleted and it is not clear what happens next to these pass-by-reference values.

[ajax333221]

the function _cloneBoardObjs() kills all references, maybe we can reuse this function.

[ajax333221]

_cloneBoardObjs() was renamed to _cloneBoardToObj(), it now returns the object it is being copied to and makes a test to make sure the board it is being copied from is actually a board. It now also copies all values (including the static ones that were previously being ignored to increase performance).

There was something tricky with w, b and squares because when doing the overwrite, some perparations had to be done that were not there.

so the references are getting unreferenced by running this line inside fenGet():

board = _cloneBoardToObj({ boardName: 'fake_board_fenGet' }, board);