Log Message:
Update from .18->.20

In brief:
46933: Update StringManager to use Java 5 features. Patch provided by Jens \ 
Kapitza. (markt)
46990: Fix synchronization issues reported by FindBugs. Patch provided by Sebb. \ 
(markt)
Allow huge request body packets for AJP13. (rjung)
Manager application prints FAIL if application was deployed but failed to start \ 
(fhanik)
When shutdown port is disabled, print user friendly message and not a stack \ 
trace. (fhanik)
The invoker servlet has been deprecated and will be removed in Tomcat 7 onwards. \ 
(markt)
45154  Implement SEND_FILE behavior for SSL connections using NIO (fhanik)

For full details see:
	http://tomcat.apache.org/tomcat-6.0-doc/changelog.html