Cacheboy-HEAD updates

I've finished cleaning up the bits of the IPv6 work from CACHEBOY_HEAD - it should be just a slightly better structured Squid-2.HEAD / Cacheboy-1.5.

Right now I'm pulling out as much of the HTTP related code from src/ into libhttp/ before the 1.6 release. I'm hoping to glue together bits and pieces of the HTTP code into a very lightweight (for Squid) HTTP server implementation which can be used to test out various things like thread safe-ness. Of course, properly testing thread-safeness in production relies on a lot of the other code being thread-safe, like the comm code, the event registration code, the memory allocation code, the debugging and logging code ... aiee, etc. Oh well, I said I wanted to..

I'm also going through and adding some headerDoc comments to various library files. headerDoc (from apple) is actually rather nice. It lacks -one- function - the ability to merge multiple files together (say, libsqinet/sqinet.[ch]) into one "module" for documentation. I may look at doing that in some of my spare time.