Matrix rotations

test.py

>>> from mathutils import Matrix, Vector
>>> axis = Vector((1,1,2))

>>> m1 = Matrix.Rotation(1.2, 4, axis)
>>> m1
Matrix(((0.46863141655921936, -0.6547330021858215, 0.5930507779121399, 0.0),
        (0.8672804236412048, 0.46863141655921936, -0.16795594990253448, 0.0),
        (-0.16795594990253448, 0.5930507779121399, 0.7874525189399719, 0.0),
        (0.0, 0.0, 0.0, 1.0)))

>>> from math import pi
>>> m2 = -1 * m1
>>> m2
Matrix(((-0.46863141655921936, 0.6547330021858215, -0.5930507779121399, -0.0),
        (-0.8672804236412048, -0.46863141655921936, 0.16795594990253448, -0.0),
        (0.16795594990253448, -0.5930507779121399, -0.7874525189399719, -0.0),
        (-0.0, -0.0, -0.0, -1.0)))

>>> m3 = Matrix.Rotation(1.2 + pi, 4, axis)
>>> m3
Matrix(((-0.1352979689836502, 0.9880663752555847, 0.07361578941345215, 0.0),
        (-0.5339471697807312, -0.1352979689836502, 0.8346225619316101, 0.0),
        (0.8346225619316101, 0.07361578941345215, 0.5458807945251465, 0.0),
        (0.0, 0.0, 0.0, 1.0)))