Akka Actors, protocol cleanup and logging - 2.9 port

Move to akka actors
Cleanup/separate protocol
Added basic slf4j/logback config

This is the 2.9 mirror of #497.  I don't think the 2.9 branch is fully updated with all master changes - so this is more a marker so that @fommil can play with it and fixup the 2.9 branch based on the updates here.

The key differences between the 2.9 and master patch are some package changes in akka and some different ask behaviour between akka 2.0.5 and akka 2.3.4