loopy unpacking and multi packing

Current implementation of persistency configures a packer and unpacker for each location. This MR changes this to:

• one packer per object type
• each unpacker for a given location also unpacks all linked locations if they are not unpacked already. This will allow to request a location to be unpacked individually.
• Packing and unpacking configurations are simplified. PersistRecoConf is removed as most of it's functionality is not needed anymore.

Part of set !3750 (merged) DaVinci!747 (merged) MooreAnalysis!92 (merged) Analysis!918 (merged) Moore!1638 (merged)

DAQ/DAQSys/python/DAQSys/Decoders.py

@@ -149,14 +149,12 @@ Decoder(
     outputs={"OutputContainerName": None},
     conf=DecoderDB)
 
-from GaudiConf.PersistRecoConf import PersistRecoPacking
 # The following decoder depends on the data type. By default you
 # get whatever is below, but "framework users" should override it!
-__packing = PersistRecoPacking(data_type='Upgrade', stream='/Event/Hlt2')
 Decoder(
     "HltPackedBufferDecoder/Hlt2PackedBufferDecoder",
     active=True,
     banks=["DstData"],
     inputs={"RawEventLocations": None},
-    outputs=__packing.packedLocations(),
+    outputs={"OutputBuffers": None},
     conf=DecoderDB)