This allows us to 'tag' the components with the correct remote ID value, which
then means we can tell where the firmware information has come from when saving
a composite store. It also allows us use the correct username and password in
the future when downloading the firmware blob itself.
Keep the old D-Bus method around to preserve API for existing clients.
Add the concept of 'remotes' that can dropped into /etc and used as firmware
metadata sources. This may be desirable when firmware is only accessable with
a valid support contract or from behind a VPN.
This allows us to return multiple results from one file, for instance where the
firmware.cab file contains multiple metainfo.xml files.
This allows us to show all the entries in the firmware file, rather than
searching for the installed device that matches and falling back to just the
first listed item.
