Merge r1458020, r1463044, r1463045 from trunk:

more simplification with ap_bin2hex()


use apr_array for an array
    
Submitted by: Christophe JAILLET (with small tweaks by myself)
PR: 52881


ap_log_error already logs the error string, no need to log it twice

Submitted by: sf
Reviewed/backported by: jim


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1470527 13f79535-47bb-0310-9956-ffa450edef68