Commit Briefs
guard against a missing SERVER_NAME
technically should always be sent; in practice don't crash if it's not set.
links: use URL if label is made only of blanks
thanks cage for unknowingly making me realize this edge case.
allow to speak "TLS-less Gemini"
useful for e.g. to save some CPU cycles when the Gemini server is sitting on the same box as Galileo; disabled by default.