Update JAR spec regarding when the last character is an EOF in a Manfiest

The JAR spec specifies the following:

- Before parsing:
    - If the last character of the file is an EOF character (code 26),
        the EOF is treated as whitespace. Two newlines are appended (one
        for editors that don't put a newline at the end of the last
        line, and one so that the grammar doesn't have to special-case
        the last entry, which may not have a blank line after it).


Manifest.java has never supported the above description. At this time, the best thing to do is to remove this from the JAR Spec