RFR 8213031: (zipfs) Add support for POSIX file permissions

[Langer, Christoph]

Hi Lance, Alan, et al.,

as it seems we are getting close to CSR approval, the changeset should also be finally reviewed.

Here is the most current version: http://cr.openjdk.java.net/~clanger/webrevs/8213031.14/

I have made some updates to ZipConstants as suggested by Lance in a private mail.

Best regards
Christoph