RFR: 8152845: Improve PackageEntry and ModuleEntry print methods for future logging

[Rachel Protacio]

Hello,

Please review this fix, moving the jigsaw PackageEntry and ModuleEntry 
print methods to product mode and making them able to take an 
outputStream. This way, we can use them for Unified Logging in the future.

Note: I changed the signature to take an optional stream rather than 
following the "print_on" scheme because the print_on function that these 
classes inherit is declared as 'const', which is incompatible with the 
non-const function calls within the print function.

Bug: https://bugs.openjdk.java.net/browse/JDK-8152845
Open webrev: http://cr.openjdk.java.net/~rprotacio/8152845.00/

Tested with JPRT and RBT quick and non-colo tests.

Thanks,
Rachel