[vector] Remove Vector.random/single/toList

[Paul Sandoz]

Here is a patch to remove Vector.random/single/toList:

  http://cr.openjdk.java.net/~psandoz/panama/vector-remove-method/webrev/ <http://cr.openjdk.java.net/~psandoz/panama/vector-remove-method/webrev/>

I also fixed some typos.

Thanks,
Paul.