Fixed typos (thanks, Bill)!
	      Added <fileVersion> element to
	      <fileHeader> element, so each
	      version of a particular DAVEfunc model can be uniquely
	      identified. Format of the version identifier is undefined.
	    
	      Added an email attribute to the <author> element. The eXtensible Name Service
	      (xns) standard doesn't
	      appear to be catching on as rapidly as hoped, so a static e-mail link will have to do
	      for now.
	    
	      Added a mandatory varID attribute to both <independentVarPts> and <dependentVarPts> so these can be
	      associated with an input and output signal name (<variableDef>), respectively.
	    
	      Added an optional <extraDocRef>
	      element to the <modificationRecord>
	      element so more than one document can be associated with each
	      modification event; if only one document needs to be referenced, use of the optional
	      refID in the <modificationRecord>
	      itself will suffice.