Allow trailing comma in settings lists

Yes! This gets me every time I copy&paste setting from the default settings file to my user file.

I concur. Even though it's not technically valid JSON syntax, I have seen a number of apps and frameworks that gracefully ignore trailing/extra commas in their JSON-ish config files. Some JSON libraries out there even support "lenient" parsing of this sort out of the box, though I imagine a simple regex substitution would do the trick.