Bug: class comment node is not updated on a class rename.
Feature: comment pane.Feature: can be unregistered from the preferences.
Bug raised by Craig: catch Cmd/Ctrl keys before they reach old code
added extensions to the attributes for merge
Merge remote-tracking branch 'origin/pharo3.0' into pharo4.0
Porting a bug correction and the comment pane on and off.
AltBrowser corner window menu: deprecated call corrected.