UV Editor

Currently, the UV editor has a bunch of confusingly overlapping tool-modes. This should all be simplified via the new active tools system.

• Split UV Editor from Image Editor
• Remove old tools panels
• Add 2D Cursor tool to toolbar
• Add Transform tool to the toolbar
• Add Grab tool to the toolbar
• Add Rotate tool to the toolbar
• Add Scale tool to the toolbar
• Add Scale Cage tool to the toolbar
• Make the Transform Scale Cage Gizmo only appear when Scale Cage transform tool is used
• Add Shear tool to the toolbar
• Fix Annotate tool in the toolbar, so that it actually works
• Add UV Sculpt tools to the toolbar
• Add Radius, Strength and the other relevant UV Sculpt settings to the tool settings & top bar
• Add Pan & Zoom gizmos in top right corner, same as 3d view.

When in the Image Editor Paint Mode, we should follow the design of the Paint modes in the 3D View, meaning;

• Tool Settings should be in top bar
• Toolbar should work the same as in 3D View