typographer can change " to ” leading to breakages in parser
At least codify this. Longer term we want to re-prioritize typographer so
it always runs after bbcode parsing.
Previously attributes such as `[test a='a"a' b="a'a"]` were not correctly
handled.
This amends the regex parser to ensure it correctly parses attributes
without breaking incorrectly on the first nested quote
Joffrey JAFFEUX
Sam Saffron
Robin Ward