Rust upgrade
Merge pull request #72 from larsbergstrom/rust_20140224

Rust upgrade
Clean rlib files
Merge pull request #73 from larsbergstrom/clean_rlib

Clean rlib files
Update to current rust: std::vec -> std::slice.
Merge pull request #74 from mozilla-servo/rustup_20140321

Update to current rust: std::vec -> std::slice.
merged from upstream; language changes: #[]; -> #![], attr matcher -> meta matcher.