- don't link gemini' /docs/ and /software/. Link the home page and let the user proceed from there - add a link to the floodgap gopher server

Initially telescope only supported about:* pages and gemini, so it made sense to set TS_VERIFIED on about pages. Now, also various non-tls protocols and TS_UNKNOWN is used more, so is more coherent to use it also for about pages.

IMSG_GET_FILE handles a path to a local file. fs now behaves like net, it sends a IMSG_GOT_CODE/META and optionally the file. This also includes a bit of refactoring: the send_file function was extracted from handle_get so it can be used in handle_get_file too.