Give PMatrix a print() method

Created by: PianoMastR64

Since PMatrix2D and PMatrix3D both have a print() method with matching signatures, it would make sense for their common interface PMatrix to have this method. Right now I have to do this:

public void printMatrix(PMatrix matrix) {
    if(matrix instanceof PMatrix2D matrix2D) {
        matrix2D.print();
    } else if(matrix instanceof PMatrix3D matrix3D) {
        matrix3D.print();
    }
}