Set up protocol messages

Adds the details for the defined protocol messages.
Parse a HeyU hub specification

This is the code to parse a hub specification.  This includes the
default port for the HeyU hub: 4859.
Create the submitter application

This is the basic submitter application (sans CERTs, for now).  The
submitter sends a notification to a hub.
Work around requirements dependency fail

For some reason, even though the requirements appear to be properly
specified for Tendril, they aren't getting installed when Tendril is
installed.  This works around the problem for the time being.