Merge r1705539, r1877263, r1877291, r1879445 from trunk:

Merge r1705539, r1877263, r1877291, r1879445 from trunk:

deduplicate the code handling the directory traversal for the
SSL[Proxy]CACertificatePath and SSLProxyMachineCertificatePath
directives

* modules/ssl/ssl_engine_init.c (ssl_add_version_components,
  ssl_init_Module): Use temporary pool for variable lookup results
  which don't need to live in pconf.

mod_ssl: Factor out code to read a BIO into a palloc'ed string:

* modules/ssl/ssl_util_ssl.c (modssl_bio_free_read): New function.
  (asn1_string_convert): Use it here.

* modules/ssl/ssl_engine_vars.c: Use it throughout.

* modules/ssl/ssl_scache.c (ssl_scache_init): Use <16 character
  cname argument for socache ->init() per the API constraint.

Submitted by: kbrand, jorton, jorton, jorton
Reviewed by: jailletc36, minfrin, jim

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1879598 13f79535-47bb-0310-9956-ffa450edef68