RFR: 8168850: Mark module entries that have been specified by --patch-module

[Rachel Protacio]

Hi,

Please review this fix, which adds a boolean to ModuleEntry to specify 
whether the module has been patched using the command line 
--patch-module. This is needed for CDS to know whether to load a class 
from the shared archive. Their tests for those changes will encompass my 
change here. I verified that it worked properly through the logging 
messages, which can be triggered with
     -Xlog:modules+patch=trace
Passes JPRT.

Bug: https://bugs.openjdk.java.net/browse/JDK-8168850
Open webrev: http://cr.openjdk.java.net/~rprotacio/8168850.00/

Thank you!
Rachel