RFR: JDK-8152691: Compare script broken after Module system

[Erik Joelsson]

Hello,

The compare script has several issues after the module system was 
introduced. I need it to be updated to a clean baseline again. Things 
fixed in this patch:

* Fixed broken conditional for jar/zip comparison
* Stop comparing jmods for now, should be redundant enough
* module-info.class needs to be compared using jdk9 javap output
* SystemModules.class has a lot of non deterministic ordering of Set 
members, making it almost always differ. Ideally this should be fixed so 
that the generator is deterministic, but in the meantime, use some 
creative sorting to work around it.
* Updated native binary comparisons with the latest from the 
build-infra/hotspot work, both for speeding up compares and being more 
accurate.

With these changes I now have a clean baseline for a full JPRT 
"buildinfra" build job of two builds with no changes between them.

Bug: https://bugs.openjdk.java.net/browse/JDK-8152691
Webrev: http://cr.openjdk.java.net/~erikj/8152691/webrev.root.01/

/Erik