- Launcher now only injects --interface/--host/--port when the matching
GRANIAN_* env var is unset, so every granian option (GRANIAN_LOOP,
GRANIAN_WORKERS, GRANIAN_HTTP, GRANIAN_HOST, GRANIAN_PORT, ...) can be
configured via granian's standard GRANIAN_* environment variables
- Add the rloop event loop as a runtime dependency so GRANIAN_LOOP=rloop
works out of the box (previously failed with a missing 'rloop' package)