Fix up tests.
Merge pull request #50 from mozilla-servo/demut2

Fix up tests.
Return a JSVal rather than a *JSVal from JS_CALLEE, to match C++.
Merge pull request #51 from Ms2ger/callee

Return a JSVal rather than a *JSVal from JS_CALLEE, to match C++.
Stop sticking things in the JSContext private.
Merge pull request #53 from Ms2ger/cx_private

Stop sticking things in the JSContext private.
Move JSVal into the jsval module.
Implement FooValue() functions.
Implement JSVal member functions to replace JSVAL_IS_* and JSVAL_TO_*.
Merge pull request #54 from Ms2ger/JSVal

Improve the JSVal interfaces.
Fix DoubleValue.
Merge pull request #55 from Ms2ger/JSVal-fix

Fix DoubleValue.
In Int32Value, cast to u32 before casting to u64.

Casting to u64 directly is equivalent to first casting to i64, which does
sign extension. For negative values, this fills the highest 32 bits with
ones rather than the zeros we need.
Merge pull request #56 from Ms2ger/JSVal-fix

In Int32Value, cast to u32 before casting to u64.
Rust upgrade
Avoid scanning stack guard page, and remove unnecessary global object rooting.
Warning police.
Merge pull request #58 from larsbergstrom/rust_20140224b

Rust 20140224b
Clean rlib files
Merge pull request #59 from larsbergstrom/clean_rlib

Clean rlib files