added test for changePlayer
passed test changePlayer
minor change to build and test
runs test isBoardFull
added test for playerMove()
passed test for PlayerMove
added another test for playerMove
passed test playerMove
added another test for playerMove
passed test for playerMove
added test for checkDiagonal
passed test checkDiagonal
added test for checkRows
passed test for check rows
added test for checkColumns
passed test for check columns
added test for checkForWin
passed test checkForWin
added test for isGameOver
passed test for isGameOver