fish: Additional GUESTFISH_* environment variables to control the prompt.

This adds:

 - GUESTFISH_INIT
 - GUESTFISH_OUTPUT
 - GUESTFISH_RESTORE

which along with existing GUESTFISH_PS1 allow you to fine control the
colour of the output.
Remove bogus license file from daemon subdirectory.

It was left over from when the daemon was a separate autoconf
directory, and in any case the daemon has never been GPLv3 (it is
GPLv2+).