Shrinksafe refactor

[Adam Peller]

Patches courtesy of Richard Backhouse (IBM Rational)

The following patch breaks apart the Dojo mods into a separate jar from Rhino, relieving us of the patch mess and more clearly delineating the MPL license, I think.

There is a compile-time dependency on JS, so the shrinksafe.jar will have to be rebuilt for new Rhino releases. There is still a problem with Rhino 1.7 (#7127)

Richard adds an -escape-unicode switch (#6628)

It also provides a new Main and a smaller set of options, so the user interface is entirely different than Rhino (though one can continue to run JS from js.jar, or compressScript programmatically by including the new jar in the classpath)

[Adam Peller]

see #7913