First draft of abnf narrative

["Lindelsee, Mike " <mlindels@visa.com>]

Well, I didn't actually stay in the office until finishing this, but did
wrap it up after getting home (and eating some dinner).  I've attached
the doc here instead of uploading it since this text does not stand on
its own and needs to be included in the main specification document.

Mike

draft-xri-v2-syntax.doc