Changes/bug fixes:
- Fixed #312 - 100% error erroneously shown in UI for GRPC tests - thanks @olimpias
- Debian sbuild working (#307) - Help to turn this into an accepted package welcome - @ldemailly
- When using the standard (slow) http(s) client, proxy settings from environment are respected (#317) - thanks @costinm
- In the UI, new + button to add more custom headers (#308) - thanks @SeriyBg