supernav_bookmark() does not "unescape" special characters like "&" in role names

Issue Summary

First of all, thanks for the great new features in Supernav! These are very much appreciated.

But I ran into a strange problem after upgrading on one of my sites (in the others, the new dev version worked flawlessly), and it took me a while to figure out what happened:

In the js function supernav_bookmark(), Supernav creates js variables for all the roles in the system, and the names of these variables are generated from the role names.

I had a role which had a "&" in its name, which broke this Supernav JavaScript. Removing the "&" from the role name fixed the problem.

"Dangerous" characters in role names are probably an edge case, so I don't think this is a critical problem that would delay a release or something. But it should be mentioned here in the issue queue in case somebody else runs into the same problem :-)