(Re)merge java.util.jar code with libgcj

[Mark Wielaard]

Hi,

I forgot to merge some small changes in the java.util.jar code from
libgcj that were made by me and Anthony Green a while back.
I have just comitted them to Classpath.

        Merge with libgcj (fixes by Anthony Green and Mark Wielaard)
        * java/util/jar/Attributes.java: Correct comment spelling.
        * java/util/jar/JarFile.java: Constructor that takes mode now
        calls super. Don't call java.util.zip.ZipFile.getEntry twice.

Cheers,

Mark