Add the original first

The only change is to the map: I'm using Ctrl-l

Source:
http://stackoverflow.com/a/6080996/79125
Add tests of original functionality

Test with a few types of braces.

All tests pass.
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 some brace tests.

Source:
http://www.reddit.com/r/vim/comments/2lnwqy/map_to_close_current_quote_bracket_or_paren/
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