Update to the last rust-nightly.

Version on rustc: 0.11.0-nightly (459f155f81291c46633e86a480628b50304ffb1c 2014-07-04 23:46:44 +0000).
Do not generate a dylib.

For some reason rustc fails to do that.
Add Cargo.toml.
Make it a dynamic lib for ease-of-use