Documentation
Check everything works:

- Run cargo update; cargo clean; cargo build
- Check in any changes

Bump version number:

- Update version number in README and Cargo.toml
- Run cargo update
- Commit changes with message 'bump version to xxx'
- Tag version-xxx

Build package locally:

- Run etc/build-package xxx
- Push master and version-xxx

Build package for trusty:

- SSH to trusty build container
- Run git pull
- Run etc/build-package xxx

Publish to cargo:

- Run cargo publish