Add built-in commands for reordering the active tab

[yyang]

Using the mouse to drag a tab left and right among its siblings is often boring. Isn't it nice to have cm_MoveActiveTabLeft and cm_MoveActiveTabRight, so that shortcut keys can be used instead?

Total Commander often looks perfectly to me. But reordering tabs requires reaching for the mouse. A big slowdown among a series of keyboard strokes. Or any better way to automate this, please?

P.S. Total Commander is one of the few compelling reasons that keep me with Windows. And the first auto-started program on my computer. Thank you so much, Ghisler.