CTR: docs

Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=56093
Provide documentation for SSLValve.
Backport of r1073184, r1568921

git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc6.0.x/trunk@1573294 13f79535-47bb-0310-9956-ffa450edef68
proposal

git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc6.0.x/trunk@1573295 13f79535-47bb-0310-9956-ffa450edef68