Improve parentheses matching

[kyrylo]

First of all, see this comment by @Mon-Ouie:

For the record, there are still things that can be improved:

Properly handling strings, and other things that use the same characters for opening and closing (%w!foo bar!)
Right now, this just inserts a "clear" code after the bracket; one could try checking the ansi codes that currently apply to make sure they aren't cancelled.

Secondly, it would be nice if we had multiline matching. But I'm not sure if that's possible.

pry(main)> def banzai(                                                                                                                              
pry(main)*     :geronimo => true) # This bracket highlights as `coolline_mismatched_paren`.

[Mon-Ouie]

Multiline matching would require getting history back to the last point where we still had parens open, which doesn't sound impossible; however I don't think we could easily change the color of parns found in previous lines.