Changes by: Aleksey Nogin (nogin at cs.caltech.edu)
Date: 2006-01-06 21:31:31 -0800 (Fri, 06 Jan 2006)
Revision: 8418
Log message:

      - Itt_nat should extend Itt_omega
      
      - Now that "meta" is a virtual theory (that is needed for "omake doc"), it
        needs to be listed explicitly in THEORIES_ALL (in mk/defaults)