Modules build minor cleanup

[Mandy Chung]

Hi Dalibor,

Can you take a look at the fix in the modules build?

1. It preinstalls the jdk modules in $outputdir
2. Not to include .map and .pdb files in the modules.  We should package 
the .map and .pdb files in some debug modules so that we can install 
them for our debugging purpose.

Webrev at:
    http://cr.openjdk.java.net/~mchung/jigsaw/modules-build-cleanup/

Thanks
Mandy