Document maxport in changes doc.
Document maxport in changes doc.

git-svn-id: https://svn.apache.org/repos/asf/jakarta/jmeter/trunk@1087983 13f79535-47bb-0310-9956-ffa450edef68

Former-commit-id: 21c9d5d0394440c7fde412ab3fd628cf0467b456
etnetera/jmeter,etnetera/jmeter,apache/jmeter,ham1/jmeter,apache/jmeter,apache/jmeter,ham1/jmeter,benbenw/jmeter,apache/jmeter,etnetera/jmeter,ham1/jmeter,benbenw/jmeter,benbenw/jmeter,apache/jmeter,ham1/jmeter,etnetera/jmeter,benbenw/jmeter,ham1/jmeter,etnetera/jmeter