Part of #35: JSON parse/unparse work units; queue pages in WU

- New shared class: page (represents results)
- Split shared classes into request and response
- Clients send JSON (response)
- Server dispenses request objects
- Refactored/renamed a bunch of stuff
- WUs include queued pages (50%+ of request)
- Replaced sun internal base64 with something else
Added missing test for pagequeue stuff in WU request
Part of #35: extract links
Resolved #35: collection and serialization of links

- Extract links (fixed regex, thanks RegexPlanet)
- Support for relative URLs