Rotation wierdness

If you print out an objects rotation that is being rotated on update on the Z axis, you see that its Z rotation is also determined by the X and Y rotation, since they switch from 0 to pi or -pi if it turns 90/180/270 degrees. This is super annoying, for example is it way harder(if not impossible, haven't tried yet) to set an objects Z rotation to Time than setting it to its Y rotation. Would be supernice if you did something about that.

Reproduce the reported behavior by rotating an object on the Z axis during update and printing its X, Y, and Z rotations. Trace the rotation handling in the engine and verify that the object's Z rotation is no longer affected by X and Y changes at 90, 180, or 270 degrees.

Written by the indexing model from the issue text.