#Support additional protocols

As mentioned in the README, I'd add like to add support for more URI schemes to HURL. Here I'll list how I might implement them:

#ftp(s):

Network.FTP.Conduit.createSource looked convenient, but will likely be incompatible with dependency versions.

Network.FTP.Client.retr, .withFTP(S), & possibly .login looks almost as easy.

#magnet:

There's a bittorrent package, but it appears to be unmaintained and not up to scratch for my needs.

#gemini:

The Network.Connection module allows me to open a TLS connection, write a line from it, and read a line from it.

mWhile (connectionWaitForInput -1) connectionGetChunk should read the full file.

May want to parse response header (after converter to UTF-8) via uncons & strip.

Since the protocol takes a URL and returns a mimetype, error code, & data it should fit right in. And it's markdown looks trivial to parse into HTML the rest of Rhapsode can handle. It should slot right in!

#gopher:

Would need more conversion effort, to extract from the URL and convert them to MIMEtypes. And if we want decent audio output, those would need to be parsed according to sometimes undefined standards.

But should be easily implementable using the same APIs as for Gemini!