Switch off of rust-postgres fork

rust-postgres no longer depends on Rust's liburl, so it no longer
conflicts with servo's liburl.
Merge pull request #7 from sfackler/stock-postgres

Switch off of rust-postgres fork
Move RequestProxy to its own file
Add a sub-router handler
Add a Head => Get translator
Namespace the entire API under /api/v1
Namespace the API under /api/v1 in ember
Search readme/description for crates as well
Add Apache/MIT license
Update dependencies and such to master
Implement the backend for keywords

* Keywords are uploaded as part of a new crate upload
* New keywords are automatically created
* Keywords contain a cache counter for the number of crates using a keyword
* API endpoints for listing all keywords and querying specific keywords
Cache keywords in crate rows and index them

Now the full text search should cover keywords as well.
Add some more tests for searching
Use names as ids for keywords
Disallow bad keywords and too many keywords
Send keywords on crate::show
Don't ever send empty keywords back
Allow searching for crates by keyword
Keywords frontend
Add an avatar component for users