Warning police.
Upgrade Rust.
Merge pull request #37 from metajack/rustup

Upgrade to latest Rust
Merge pull request #38 from jdm/tracehook

Add finalize and trace hooks for proxies.
Upgrade Rust.
Merge pull request #40 from metajack/uprust

Upgrade Rust.
Take scripts as ~str to support non-ASCII string literals etc.

The ASCII-based JS_EvaluateScript converts to UTF-16 internally, so this
shouldn't be fundamentally worse (but I haven't benchmarked the two conversion
routines or anything).
Merge pull request #41 from kmcallister/jsstr

Take scripts as ~str to support non-ASCII string literals etc.
Fix broken test case
Merge pull request #42 from kmcallister/jsstr

Fix broken test case
fmt! -> format!
Upgrade Rust
Merge pull request #43 from kmcallister/rust-upgrade

Rust upgrade
Derive jsval cloning.
Add FFI for js::GetGlobalObjectCrossCompartment.