use crates.io in README
Merge pull request #33 from steveklabnik/master

use crates.io in README
Update tests to rust master
Add keywords to cargo metadata.
Update to iter stabilization.

`AdditiveIterator::sum` and `MultiplicativeIterator::product` now take bare self.
Merge pull request #34 from gifnksm/master

Update to iter stabilization.
Bump to 0.0.5.