Rust <1.7 compatibility broken in #106 due to use of String::as_str

[kamalmarhubi]

Compatibility and semver seem contentious, but I just wanted to point this out. It's a tiny change to support 1.2 so I'll send the tiny PR to do so in a bit.

[kamalmarhubi]

Actually since String::as_str was stabilized in 1.7, this drops support for all earlier versions.

[alexcrichton]

Ah certainly unintentional! Feel free to send a PR!

[kamalmarhubi]

This was fixed in #110 which you just merged!

[fiveop]

Since this broke builds, I kindly ask for a new release.

[alexcrichton]

Published!