[Halld-offline] Two checked in versions of the xstream headers

[Mark M. Ito]

Folks,

There are inconsistent versions of the xstream headers checked into the 
src tree. In particular they are in the xstream/except directory (which 
occurs in two places in the src tree).

Don't know how to resolve this. More on the problem at:

   
http://markito3.wordpress.com/2010/02/05/two-checked-in-version-of-the-xstream-headers/

   -- Mark