Fixed type serialization problem in ServiceDiscoveryProtocol
Improved upload code to avoid unnecessary TCP connection handshake
Started to implement proper shut down of BLOB server
Introduced BLOB cache to locally cache content-addressable BLOBs
Implemented lookup of BLOB server address for task managers
Added first implementation of BLOB cache
Added Apache headers to BLOB service files
Added javadoc to BLOB cache
Added unit test for BLOB cache