daemon: Respect fragmentation support in API registrations

Now, the API will only announce bundle fragments if fragmentation support
is disabled. Otherwise, the bundles will be reassebled first and then delivered.
daemon: Remove "wait for empty buffer" condition on close() in DatagramConnection
daemon: Use extended SDNV comparison in NodeHandshake de-/serialization
ibrdtn: More operators in SDNV template
daemon: Check is a bundle is already marked as removed before queuing a remove task
android-daemon: Add fragmentation support option to the daemon preferences