jigsaw builds

[Jonathan Gibbons]

The jigsaw modules builds do not include src.zip and the demo and sample 
directories.

Is this intentional, accidental, or just "not got around to it, yet?"

> $ ls build/linux-amd64/j2sdk-image/
> ASSEMBLY_EXCEPTION  bin  demo  include  jre  lib  LICENSE  man  
> sample  src.zip  THIRD_PARTY_README
> $ ls build/linux-amd64/jdk-module-image/
> ASSEMBLY_EXCEPTION  bin  include  lib  LICENSE  THIRD_PARTY_README

-- Jon