rpm unpacking shpuld create a RPM_META directory containing
 - unpack normally, then 

 - mkdir .RPM_META or .RPM_META_nnn (lowest number that is available)
 - a full dump of al headers
   rpm --querytags | xargs rpm -qp --qf '$NAME = %{$NAME}\n' >> .RPM_META/tags
 - expose all scripts explicitly
   rpm --showrc  >> .RPM_META/scripts
 
 - see if filename RPM_META is unused, 
   make a symlink to the .RPM_META* dir we used above.

implement multipart mime encoded archives. test.mht
