Support the LDP API (and clean up our internals in the process)

Fedora 4 should be LDP compliant. To become compliant (and keep things reasonable), we need to clean up our HTTP API internals for consistency and clarity. 

https://www.pivotaltracker.com/story/show/79973150
https://www.pivotaltracker.com/story/show/79703120
https://www.pivotaltracker.com/story/show/59232134
https://www.pivotaltracker.com/story/show/76048574
https://www.pivotaltracker.com/story/show/60441592
https://www.pivotaltracker.com/story/show/71751536
https://www.pivotaltracker.com/story/show/70600504
https://www.pivotaltracker.com/story/show/78034072
https://www.pivotaltracker.com/story/show/61391216