[vector-unstable] remove benchmarks

[Paul Sandoz]

Hi,

Please review the following to remove the benchmarks and associated template files from the vector-unstable branch:

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

We decided to propose the benchmarks separately to that of integration for ease of review.

Paul.