Fix another part of #35141: there was no way to reset the stencil transform after e.g.
scaling it along one axis, now there's a Reset Transform button.

The Image Aspect button is now also hidden unless the texture is an image texture.
And also hide the color wheel for painting tools that don't use colors.

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@56411 954f8c5b-7b00-dc11-b283-0030488c597c