Followup to r1565163
Catch exceptions thrown by getParts() and report them as other upload errors 
(in the message box on the HTML page).

Without this an uncaught exception resulted in Error 500.

I am removing warPart cleanup code, because Tomcat already does such cleanup when Request is recycled
(Tomcat code deletes all parts in a request, and part.delete() could throw an IOException).

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1565300 13f79535-47bb-0310-9956-ffa450edef68