Blender Git Loki

UI: Sculpt menus cleanup

This removes the Brush pulldown menu from Sculpt and Paint modes. This menu only contained a random duplicated subset of brush options. Now everything is accessible centrally in the Brush Tool Settings.

The Sculpt menu likewise contained various random brush options. These are removed and replaced by a list of commands, just like the other paint modes.

Also removes the Show Mask option from the mode options panel since this is also in Overlays.

Reviewers: Campbell Barton

Differential Revision: https://developer.blender.org/D5420