WordPress ignore rules: update to Class::__construct instead of the old 'new Class' convention

This was overlooked when I decided to ignore class constructor
arguments via ‘Class::__construct’ instead of ‘new Class’.
Ignore HTML fragments like " class="">, or " alt="" />, add to related unit tests
Don't keep from ignoring strings with a leading underscore, add to related unit tests
Remove unused method

Remove the exclude_dirs() method, which isn’t being used, since
excluding directories isn’t currently supported.
Function declarations: Prefix class methods with class name; add related unit tests

When in a class, we switch out `$this->` and `self::` for `Class::`.
Now we’ll do the same thing for class method declarations.
Remove some extra newlines.
Update @version (forgot this before, oops)
Correct command line tests @group
Error reporting: show the full function-call stack, or the attribute name if in an HTML attribute
Re-parse files with errors in them, even if the cache indicates they haven't changed
Remove @todo which is no longer needed
Ignore child class methods if the method is ignored in the parent class

So if `Parent_Class::method` is in the ignores list, then
`Child_Class::method` will inherit that, and be ignored as well.

Also adds related unit tests.
Make sure to reset the current attribute to false
Capitalize "debug" in the debug message.
Count some tokens as opening braces, since they are paired with closing braces
Follow chained method calls within classes, add related unit tests
Object dereferencing: we can't get the class name, so report it as '(unkown)' rather than ignoring it.

Formerly if we couldn’t get the class or variable name that the method
was being called from, we just reported it as a non-OO function. This
was confusing and could cause the parser to ignore it unintentionally.

Adds related unit tests.
Add to the ignores lists.