Rewrite the PHP parser as a real parser, not using regexes. This is
more complex but allows for better parsing.
Visible changes:
* Scope reporting;
* Variables inside functions are no longer reported (this is a
deliberate choice, but can be easily changed);
* Only the PHP part is parsed (e.g. it doesn't report JavaScript
functions anymore);
* Function arguments spanning several lines are properly reported;
* Interfaces are not yet parsed.
Otherwise the new parser should behave like the old one, at least
where it used to be right. Parsing of more constructs and reporting
more details is planned.
be07870e97