Bump httparty from 0.13.0 to 0.15.5
Bump httparty from 0.13.0 to 0.15.5

Bumps [httparty](https://github.com/jnunemaker/httparty) from 0.13.0 to 0.15.5.
- [Changelog](https://github.com/jnunemaker/httparty/blob/master/Changelog.md)
- [Commits](https://github.com/jnunemaker/httparty/compare/v0.13.0...v0.15.5)
theodi/open-data-certificate,theodi/open-data-certificate,theodi/open-data-certificate,theodi/open-data-certificate