Follow up to r1833368: share openssl between modules.

Both libapr[-util], mod_ssl, mod_crypto and mod_session_crypto can use the
same crypto library (e.g. openssl), use the new APR crypto loading API so
that they can work together and initialize/terminate the lib approprietly,
either once for all or on demand and reusable by the others.



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1833452 13f79535-47bb-0310-9956-ffa450edef68