Update to sublime-syntax

[ehuss]

I'd like to fix some of the bugs in the TOML highlighting, and before doing that I think it would be nice if this was updated to sublime-syntax, possibly updated to conform with Sublime 3's scope naming rules, and include syntax tests.

@Jayflux I'd be happy to work on these changes. Would you be OK with a PR for this?

[jasonwilliams]

@ehuss absolutely
I was going to do it myself but ive completely ran out of time lately.

Thanks for picking this up

[ehuss]

I hope it's the good kind of busy and not the annoying kind.

I just opened a PR with the changes. No rush to look at it, of course. I broke it up into separate commits to maybe make it easier to see the individual changes. There are a lot of judgement calls for things like scope naming and how aggressive to be with error highlighting. Feel free to send me whatever feedback or questions.