serious bug fix:

  htdigest didn't init the first parm to ap_open(), so ap_open()
  segfaults thinking it was passed valid storage
build portability:
  make most src/lib/apr/test/Makefile.in compatible with OS/390
  make (no -o outfile after infile specified)
MD5 translation support:
  when APR_HAS_XLATE, low-level routines allow translation handle
  to be specified

  when CHARSET_EBCDIC, password-specific routines always translate,
  but client app must set handle before using


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@85160 13f79535-47bb-0310-9956-ffa450edef68