Merge pull request #30 from sebcrozet/master

Update to the last rust-nightly.
Updated for latest Rust
.travis.yml: Download latest nightly from rust-lang.org
Merge pull request #31 from ozkriff/master

Updated for latest Rust
Updated to latest Rust: ~str -> StrBuf
Merge pull request #32 from ozkriff/master

Updated to latest Rust: ~str -> StrBuf
Updated to latest Rust
Merge pull request #33 from ozkriff/master

Updated to latest Rust
StrBuf->String
Merge pull request #34 from bjz/string

StrBuf->String
Updated to latest Rust: to_strbuf -> to_string
Merge pull request #35 from ozkriff/master

Updated to latest Rust: to_strbuf -> to_string
Update to latest rust.
Merge pull request #36 from phaikawl/master

Update to latest rust.
Update to latest rust nightly
Merge pull request #38 from bjz/update

Update to latest rust nightly