Proposal: new default bindings for winner and windmove

[Daniel Colascione]

Today, winner binds C-c LEFT  and C-c RIGHT for window configuration 
undo and redo, respectively. This set of bindings has three problems:

 1) the bindings occupy binding space on important keys, LEFT and 
RIGHT, for functions that are rarely used,

2) the winner binding space isn't logically connected to window 
management, and

3) the bindings don't work on terminals without LEFT and RIGHT.

How about we set up these bindings instead?

C-x 4 C-/ winner-undo

M-- C-x 4 C-/ winner-redo

This way, a winner undo has the same binding as editing undo, but under 
C-x 4, which means window management stuff.

(Also: is there any reason we shouldn't enable winner by default?)

Likewise, for windmove, we can bind C-x 4 {left, right, up, down} and 
DWIM for people automatically, enabled by default.