changed a few "is not" to !=

this is more technically correct
added space in print function
added debug_WhosTurnGenerator to tests

this tests the WhosTurnGenerator function
debug_swap_players: switched list handling bugfix

'for [value] in list:'
make python complain.
debug_swap_players bugfix

was comparing enum objects with values
I am now comparing the values of enum objects with values
(now say that 5 times fast)
board_array_documentation change
added assertions to check_board
removed assertion from check_board_diagonally

these assertions are now done in main
redid assert statement in swap_players

now using enum for testing that the player value is correct
clarified passing of list to check_for_assertion_error
Revert "clarified passing of list to check_for_assertion_error"

This reverts commit 075904ed8f2ec757590ef39d06a5974f23356f44.
Revert "Revert "clarified passing of list to check_for_assertion_error""

This reverts commit b699eb88d47b07ea8d2c4af1f3af14afba3c4ff2.
added get_diagonals function

get_diagonals takes an nxn board_array and returns a tuple:
(down_right_diagonals, up_right_diagonals)