RFR: JDK-8199681 Remove boilerplate code from creating native jtreg tests

[Magnus Ihse Bursie]

There's currently a lot of boilerplate code needed to setup a new native 
jtreg test. This was never the way it was intended to work -- the idea 
was that you basically should just add the file and then things should 
work automatically, unless you had special requirements.

This patch will make it so once more.

I have tested this using COMPARE_BUILD. I get some spurious binary 
differences on macosx. I can't really say why, but then again, we have 
never verified the test image by a clean "back-to-back" null comparison 
either, so I'm not worried. Apart from that, it looks green.

Bug: https://bugs.openjdk.java.net/browse/JDK-8199681
WebRev: 
http://cr.openjdk.java.net/~ihse/JDK-8199681-remote-native-test-boilerplate/webrev.01

/Magnus