Multimap Bucket can't get replicated in server mode

Mulitmap put/get only sends the function over the network, which works fine. But, if you have to replicate the Bucket class, it will fail (state transfer & cross-site are 2 examples)

This happens because of MultimapRequestProcessor which wraps the user's key & value with WrappedByteArray and the "user marhsaller" is unable to handle WrappedByteArray. Wrapping the keys & values with WrappedByteArray is no longer necessary and it should be removed.