In the unified-transform, scale, and perspective tools, take the
maximal transform-grid handle size into account when readjusting
the transform, so that the handles themselves are fully within view
under arbitrary rotation, rather than just the corners.
(cherry picked from commit 46e16e175c)
Simply use g_object_bind_property() to connect the grid properties of
GimpTransformOoptions and GimpToolTransformGrid and remove all other
grid property setting code.
