Identification
Image transfer
Imaging
Automatically ReleaseDevice when application disconnects from bus
Rethink print handling - we discover on ListEnrolled and rediscover on each LoadPrintData

Enforce command sequences:
 force VerifyStop after non-retry verify result comes in
 only allow GetVerifyResult during a verification
 only allow VerifyStop during a verification
 etc


- Make storage handling a GObject interface, would make plugging in new
  backends easier, even handling plugins?
- Make storage per-manager
- Move storage setting to a configuration file
- Kill FromStorage variants, we should always load/read from our custom storage