[REQ] Improved Tabs

[majkinetor !]

There is a lot of empty space there in panels.... I thought it would be nice to have some buttons there like we already have in regular panel caption (* and \/ ). For instance most usefull functions like [x] close tab, [ ] lock tab can be placed there. It would improve tabs functionality a lot.

I know that we have middle mouse button to close but tell that to the newbee....

[Balderstrom]

Why not make it into an edittable command Menu that takes 17x16, or 17x17 icons (not sure what size the buttons are)