mod_ssl_ct: Work with current Certificate Transparency tools

(e.g., as of certificate-transparency commit 
3f03188fe89974d45345fddee64a8227bd2ec26a)

The interface to the "ct" tool now requires the log's URL and
public key, resulting in a bit of refactoring in the module.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1630624 13f79535-47bb-0310-9956-ffa450edef68