moved method isEmpty out of class
moved method isEmpty() out of class Matrix
moved method isNull() out of class Matrix
moved method isNull() out of class Matrix
removed early declaration of function isNull() because of it's useless
at class Matrix
moved out method haveSameSize() from class Matrix
fixed early declaration of function haveSameSize()
moved out method isSquare() from class Matrix
added case AllCases to test MatrixIsSquare
fixed places of usage method isSquare()
moved out method isZeroMatrix() from class Matrix
moved constants DETERMINANT_OF_MATRIX_0X0 and
DETERMINANT_OF_MATRIX_WITH_ZERO_ROWS_OR_COLUMNS to MatrixAlgorithms.h
moved out method getRowVector() from class Matrix
moved out method getColumnVector() from class Matrix
added case Matrix3x3 to test MatrixGetColumnVector
added case EmptyColumnCases to test MatrixGetColumnVector