Review request: 7120875 fix macos ipv6 issue and update multiple test scripts

[Michael McMahon]

Hi,

This webrev fixes a bunch of test script issues in networking and core-libs.
In most if not all cases, the change relates to recognising the OS that 
the test
is running on.

It also fixes an IPv6 issue, which requires Macos versions of a couple 
of java.net
classes. These are the new files at the end of the webrev. The change is 
to provide
a default sin6_scope_id when none is provided by the user.

http://cr.openjdk.java.net/~michaelm/7120875/webrev.1/

Thanks,
Michael.