upgrades rocket to 0.5

[Maweypeyyu]

This changes/fixes/improves …

• [x] I have read the contribution guidelines
• [ ] This change has tests (remove for doc only)
• [ ] This change has documentation
• [x] Corresponds to issue (#131)

I license past and future contributions under the dual MIT/Apache-2.0 license, allowing licensees to chose either at their option.

Let me know if I can improve anything.