another vote for making default menus mutable

[Xavier Toth <txtoth gmail com>]

We are developing a MLS (multilevel security) system on top of Fedora
and SELinux. A number of the directories and files accessible to the
user are polyinstantiated based on the context range (ex.
UNCLASSIFIED, CONFIDENTIAL). Because of this we'd like to be able to
override the functionality of things like 'Create Folder'  and 'Copy'
so that they can properly deal with polyinstantiation.

Ted