Diffa Diffa

The file participant is in some need of an overhaul:

• It doesn't create the config data it needs to in order to get the agent to start matching for it
• It hard codes the agent URL which makes it difficult to re-point
• It uses maven to boot itself - whilst this is convenient to set up the classpath, it makes the log output more verbose and less intelligible
• It doesn't print out what is going on, either on start up or as RPCs come in
• There is no test for this (and hence is not part of the TC build)
• There is no README

Since other language clients might port this to do their own integration tests, I think that we should spend some time cleaning this up.

Also, seeing as IPC between the participants is achieved via the file system, maybe their is an opportunity to carve out some kind of test scenario that can serve as a TCK (see #4 for some background).