[sr-dev] path module rewrite/additions

Hello, Since this is a significant rewrite of an existing module, I'd like to ask if anyone has any objections against committing the attached patch. Functionally, it adds a second parameter to add_path() and add_path_received(), enabling the script writer to include arbitrary additional URI parameters in the Path header. It also adds support for SPVE for all parameters. Code wise, it rewrites most parts of prepend_path() to make the code more streamlined, use fewer memory chunks and lumps and (hopefully) make the code easier to read, shorter, and easier to extend in the future. I'm attaching the new path.c as well for readability. I haven't included the updates to docs. cheers