Rackspace CLBs

Addresses #289. Milestones are:

- [x] LBs
- [x] error pages
- [x] LB stats
- [x] nodes
- [x] VIPs
- [ ] domains
- [ ] usage reports
- [x] access lists
- [x] monitors
- [x] session persistence
- [x] connection logging
- [x] throttling
- [ ] caching
- [x] protocols
- [x] algorithms
- [x] SSL termination
- [ ] metadata

(Not sure if all of these resources will make it into this PR)
Personally, I prefer the shorter version because it seems in keeping with how other go packages name things, and also because users will most likely understand what functionality is housed within `acl` or `lbs`. If we look at standard packages, they use abbreviated forms: `bufio`, `crypto`, `expvar`, `fmt`, etc.