RFR: JDK-8082537 - jimage should print usage when started with no args

[Jim Laskey (Oracle)]

It can be outside, does the change add value?

> On Apr 22, 2016, at 10:12 AM, Jim Laskey (Oracle) <james.laskey at oracle.com> wrote:
> 
> Now prints usage.
> 
> http://cr.openjdk.java.net/~jlaskey/8082537/webrev/index.html <http://cr.openjdk.java.net/~jlaskey/8082537/webrev/index.html>
> https://bugs.openjdk.java.net/browse/JDK-8082537 <https://bugs.openjdk.java.net/browse/JDK-8082537>
>