This change addresses two issues with commands that re-used
flags from common packages:
1) cobra.Command definitions did not include the command specific
prefix in doc strings.
2) Command specific flag prefixes were added after generating
command doc strings.
- add support for unix sockets (which skip the auth).
- add support for multiple listeners
- collapse unnecessary internal structure of lib/http so it can all be
imported together
- moves files in sub directories of lib/http into the main lib/http
directory and reworks the code that uses them.
See: https://forum.rclone.org/t/wip-rc-rcd-over-unix-socket/33619Fixes: #6605
