Rename some xul ids
Change listing xul element in Permissions dialog

From listbox to tree. Because we already use tree on
other places in code and have javascript module for
more convinient way of building this tree.
List of possible permissions assignees
Fix sorting lists of users/groups

in Permissions and Properties dialogs.

Sorting is now natural and case-insensitive.
Also it used to be sorted using whole label
which for user is realname + <username> and caused
wrong results.

Third party sorting algorithm is used.
https://github.com/overset/javascript-natural-sort