[osis-core] Alpha attached, needs two regexes - No regex on sID and eID

[Todd Tillinghast]

Patrick,

We talked about the need for a regex for sID and eID after you were off
the call on Friday, and the conclusion what to leave the attributes with
no regex in the same fashion as the now retired splitID, which was
xs:string plain and simple.  

Steve suggested restricting sID and eID to XML Names, but Troy reminded
us that we would want to allow simple osisIDs to be used which can start
with numbers.

Todd