Changes

Vetter objectpooled vec class and blas1 vecops

This should be the replacement for Vn.

Implements a 2^n length objectpool and a bunch of blas level1 APIs
and some helpers for writing RK methods.

Ports over the use of Vn in the AutoDiff module to Vec.

Vec does not zero-initialize by default.
 (commit: 732b3db)