Adding classes to issue queries for and respond to version requests in ralph.
Updated build directory to build versioning code as well.
Started adding infrastructure for exchanging versioning messages.
Removed some dead code.
Need mechanism to serialize updates as response to version queries (which aren't implemented yet).
Added several additional logging fields to specify device updates.
Adding a uuid message type for versioning protocol buffers.  It's kind
of gross that I'm reproducing the uuid message type from the regular
ralph protocol buffers, but I thought it was a better idea to isolate
the two protocol buffer libraries as much as possible.
Adding a protocol message type that effectively serializes a SingleDeviceUpdate instance.
Adding auto-generated version messages.  Adding auto-generated code instead of actually generating sources each time, so that I do not have to maintain a protocol buffer library dependency.
Upgraded protocol buffer dependency to use code generated from 2.5.0 compiler instead of 2.4.1.
Serialize update messages for each SingleDeviceUpdate.