Merge pull request #148 from ozkriff/master

.travis.yml: Download rustc from rust-lang.org
Use bitflags! to implement Modifiers
Merge pull request #149 from bjz/modifiers

Use bitflags! to implement Modifiers
Replace ~ with Box and box where appropriate

With this commit, the code compiles with the latest Rust version.
Bring code up to date with local_data API changes
Merge pull request #151 from hannobraun/rust-upgrade

Upgrade to latest Rust
Update to nightly
Merge pull request #152 from bjz/update

Update to nightly
std::cast::transmute -> std::mem::transmute
Merge pull request #153 from alexanderchr/master

std::cast::transmute -> std::mem::transmute
Updated for latest Rust