Update most `~str` things to `StrBuf`.
Update for Result-yielding Decodable::decode().
Rename crate roots to lib.rs (convention).
Use new inner attribute syntax.
Update for struct publicity swap.

(Used to be public by default, private when marked explicitly; now it's
private by default, public when marked explicitly.)
Update rust-phf
Update macros crate for new Rust
Update tests and benchmarks for new Rust
Note Rust version in README
make check: Check that everything builds
Hack rust-phf build into the Makefile

Recursive make :(

Should do something better eventually.
Add Travis CI integration
Add build status to README
Intern a static set of strings

The list of static atoms was extracted from Gecko's {Element,Attribute}Name.java.
tokens.rs -> interface.rs, and define TokenSink there
Rust upgrade
Make warnings fatal
Update travis.yml to use nightly tarballs
Remove workaround for fixed Rust JSON bug
Tokenizer test cleanup