RFR: JDK-8231882: --add-modules ALL-MODULE-PATH is not handled properly

[Andy Herrick]

Please review the jpackage fix for bug [1] at [2].

This is a fix for the JDK-8200758-branch branch of the open sandbox 
repository (jpackage).

This change eliminates the ModuleManager class and uses ModuleFinder 
class to locate modules.

[1] https://bugs.openjdk.java.net/browse/JDK-8231882

[2] http://cr.openjdk.java.net/~herrick/8231882/

/Andy