Apparently removeSelector: does not dirty packages...

For example

Workspace removeSelector: #embeddedInMorphicWindowLabeled:!
does not make the package dirty.

This can be normal because this is a low level API method. Now this expression is saved in the changeset
when we remove a method. So the task to do is:
   - check if there is another API method that raise the correct notification of changes
   - change ChangeSorter to use this api


http://code.google.com/p/pharo/issues/detail?id=3714

Stef