This updates archive to use new header information in az files and makes way for combining the meta data file with the AZ file. 


storage/archive/azio.c:
  This removes the default gzip information and now uses a custom header.
storage/archive/azlib.h:
  Additions for custom header and future meta data.
storage/archive/ha_archive.cc:
  Removed data header in favor of new header system.
storage/archive/ha_archive.h:
  Removes data_version