Bump failure from 0.1.4 to 0.1.5 (#82)

Bumps [failure](https://github.com/rust-lang-nursery/failure) from 0.1.4 to 0.1.5.
- [Release notes](https://github.com/rust-lang-nursery/failure/releases)
- [Changelog](https://github.com/rust-lang-nursery/failure/blob/master/RELEASES.md)
- [Commits](rust-lang-deprecated/failure@0.1.4...0.1.5)

Signed-off-by: dependabot[bot] <support@dependabot.com>