Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=56365
Improve documentation, update changelog.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1590318 13f79535-47bb-0310-9956-ffa450edef68
Correct formatting and a few minor typos.
No substantial changes to the text.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1590322 13f79535-47bb-0310-9956-ffa450edef68