DeviceServiceImpl: do not fail when a device is missing a type
DeviceServiceImpl: do not fail when a device is missing a type

When fetching devices, it maight happen that something goes wrong.
Here we handle the case, when the Dao layer did not recognized the
device type (changes in devices.xml incompatible with database state).
Devices which are having issues are simply skipped with a record
in log.

Signed-off-by: Jan Viktorin <3eab6ac54c005c4408f608556a6663b7f2abede7@fit.vutbr.cz>

BeeeOn/server,BeeeOn/server,BeeeOn/server,BeeeOn/server