Update JMeter from 2.5.1 to 2.7 -- the latest at this moment. Re-arrange
the port to depend on JAR-files already provided by other ports, instead
of installing its own (bundled) versions of same.
Rename from "jakarta-jmeter" to simply "jmeter" -- according to Apache
site, Jakarta is no more and all its projects now live on their own.
Take over maintainership.
Approved by: beat (the previous maintainer)