Vectorization Stuff-- Round I

Adds the following functionality:
* Dot Product * for 1D vectors and 1D vectors of variables
* Dot Product * between 1 by _n_ vectors and _n_ by 1 vectors of variables
* bigdot(A,B), a matrix inner product between two similarly dimensioned matrices.  For 2D matrices, bigdot(A,B) = trace(AB'). Performs the natural extension for 3D matrices. 

Also includes a speed testing script for these options.