Added extra error checking to help debuging.
Added htmltidy to the build process.
Removed hardcoded urls. These will be set by the subclasses.
Made grab post page virtual because some chans don't display full pathnames in their HTML source.
Hardcoded URLs must end with forward slashes to avoid unecessery string logic.
Added extra logic to deal with unqualified image URIs. This logic may need to be moved since other sublasses will probably need it.
Interface for new method.
Removed debugging code.