RFR: JDK-8145789: Switch JDK 9 to use Jib in JPRT

[Tim Bell]

Erik:

> With Jib support in JDK 9, it would be nice to start using it in JPRT 
> instead of having JPRT having to track dependencies and 
> configurations. This change enables Jib in JPRT and disables all the 
> JPRT functionality for tracking dependencies (build.needs and most 
> configure args).
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8145789
> Webrev: http://cr.openjdk.java.net/~erikj/8145789/webrev.top.01

Looks good to me, as long as test builds work OK.

TIm