Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=57238
Update information on SSL/TLS on Security and SSL documentation pages.
Patch by Glen Peterson minus mention of OpenSSL syntax for ciphers attribute in security-howto.xml, as that feature is unavailable in Tomcat 7.

Merged r1644333 from tomcat/tc8.0.x/trunk (r1644321 from tomcat/trunk).

git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc7.0.x/trunk@1644339 13f79535-47bb-0310-9956-ffa450edef68