This will allow to pass quoted arguments and some variable expansion. Basically
one-line shell command service can be embeded in the configuration.
In previus version use of "command path with spaces" whould result in try to
execute '"command' with arguments 'path', 'with' and 'spaces"'.
Most qrexec services doesn't use remote domain name, as policy is enforced
earlier. So pass it in way that will allow use of generic command as qrexec
service.