On the svn-auth-x509 branch, make the x509 parser return an APR hash table
containing cert information, instead of a custom x509 cert structure.

* subversion/libsvn_subr/x509.h
  (SVN_X509_CERTINFO_KEY_ISSUER,
   SVN_X509_CERTINFO_KEY_VALID_FROM,
   SVN_X509_CERTINFO_KEY_VALID_TO): New hash key macros.
  (svn_x509_parse_cert): Change output parameter to apr_hash_t **.

* subversion/libsvn_subr/x509parse.c
  (): Include svn_hash.
  (svn_x509_parse_cert): Return certificate information in a hash table.
   For now, values are rendered just like 'svn auth' printed them.

* subversion/svn/auth-cmd.c
   (show_cert): Adjust caller.


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/svn-auth-x509@1605052 13f79535-47bb-0310-9956-ffa450edef68