Screed 1.0 Release Candidate Prep work

Right. So.

 - [ ] write screed release docs
 - [x] install/run versioneer
 - [ ] update relevant docs (known_issues, etc.)
 - [ ] make shiny new packages
 - [ ] do release?
Would the best way to do this be to launch a python prompt, import screed and have it print its version, as screed doesn't have standalone installable scripts?