RFR 7902018: Enhance NB project to support tests

[Alexandre (Shura) Iline]

Hi.

Please take a look on this change. Instead of a free-form NB project, which was there before, I now use usual Java project, only redirecting the source and test trees to the upper level. That works much better.

Bug: https://bugs.openjdk.java.net/browse/CODETOOLS-7902018
Webrev: http://cr.openjdk.java.net/~shurailine/7902018/webrev.00

Thank you.

Shura