For updater: Assorted cleanups and fixes

This PR just has a couple of quote-escaping cleanups, etc which I did quite a while ago and didn't even realise I hadn't committed or PR-ed them yet (oops).

BTW: When I last had time to work on the updater (after the above fixes) I abstracted it and did loads of refactoring to the point that it is 95% able to work as a generic django-app-updater rather than just a servermon-updater :-) I tried it on a few other django-apps with about 95% success :-/ The key part of that sentence is the not-quite-100% bit though, hence why I haven't made any of that branch public yet. As so painfully often happens though the rewrite had to take a back-seat while other priorities were pushed forward, so it has languished on my hard-drive for months since then. When I get the chance to finish readying it for release (i.e. not exiting prematurely) I think it would make sense to upload it as an independent tool due to it no longer being servermon-specific (which would help making it robust more quickly due to input and updates from other django users). Let me know if you agree. If/when I do that you could either make it a git-submodule or just link to it in the docs for those servermon users who want to try using it, etc...