Use solution from reddit that adds quote support

Instead of just braces, it closes quotes. This is trickier because they
are unmatched, so we need to do some magic to guess what's the right
thing.

Breaks brace tests.
Add tests for how it should work

Some tests fail. Not sure what needs to change to make this work.

After closing quotes, it will keep adding quotes and not find the
preceding parens.

For some reason closing include strings fails. Possibly a different kind
of string syntax attribute.
Refactor synIDattr into is_string