Switch java recommendation to suggests

This gets around a rather insane set of circumstances wherein Berkshelf
won't let you ignore recommends [1]. Basically, Berkshelf will always
download a recommends, but not a suggests, so if we downgrade this
keyword (which is of course meaningless in Chef terms), then we can
still appease Berkshelf but also let users know Java is a system
requirement.

[1] https://github.com/berkshelf/berkshelf/issues/895