Summary: updated try-with-resourcse usage in test/demo code
Reviewed-by: alanb

7014948: (zipfs) ZipFileSystem.newFileSystem(Path...) should not throw FileSystemAlreadyExistsException
7015139: (zipfs) ZipPath.delete() should throw DirectoryNotEmptyException when handling "real, non-empty" dir
Summary: zip filesystem provider update
Reviewed-by: alanb

7009092: (zipfs) ZipPath.isSameFile() should always return true if this Path and the given Path are equal.
7009085: (zipfs) ZipPath.normalize("/./.") returns null.
7009102: (zipfs) ZipPath.toRealPath() should always return absolute path.
Summary: zip filesystem provider update
Reviewed-by: alanb

Summary: zip filesystem provider update, add zipfs.jar into ext dir
Reviewed-by: alanb

6994161: (zipfs) newFileSystem method should FileSystemAlreadyExistsException
6994152: (zipfs) copyTo ignores COPY_ATTRIBUTES option
Summary: zipfile update
Reviewed-by: alanb

Summary: The first drop of the zip filesystem provider, as a separate demo
Reviewed-by: alanb