progress reporting
	+ seems not to work - I get 0%'s for most things (why?)
	+ particularly (eg.) updating a lot of packages; most odd.
		+ we get signals starting / finishing packages etc.
			+ but nothing more (?)
		+ do we only notify on a 'sub' progress %age ?

cancallation ...
	+ lots of threading nasties here

Root handling
	+ get_zypp needs to handle multiple roots properly /
	  more carefully.

package updating
	+ re-test patch updating carefully
	+ ensure no packages overlap with patches etc.

pkcon remove glibc
	+ morphs the remove into an install (somehow)
	+ doesn't complain that we might destroy the system
	+ OTOH: doesn't destroy the system 

implement backend_download ...
	+ essentially an install with --download-only set to true.

NEWEST handling
	+ should move from backend_resolve_thread to
	+ zypp_emit_filtered_packages_in_list
		+ where it can be shared & more generic
		+ will require calculating 'newest' per package
		+ which would make that method more efficient anyway

PkBackend
	+ if/when this is switched to a GObject - we need to sub-class
	  and store our (currently) static pointers on it for elegance's
	  sake - also to allow 'destroy' to do a better job there.

