Rotate edges was unfinished still, and not supposed to work on large
selections. Code cleaned up some, and restricted to work on a single
selected edge, or two adjacent selected faces.
Also changed menu description, and give error() on wrong selection.
2) Fix for undo mixup in texteditor
Global hotkey list now passes on ctrl+z (global undo) to local queue
in textwindow. (Also for ctrl+y). Scriptwindow also doesn't accept
global undo key.