header downsizes for a smaller example and beamformer adjusts magic
numbers for setting up dimensions to support that.

init method setups up the weights instead of only being loaded by a
file, this makes `cublas_main` unusable but this is for setting up to
verify output and be able to start making adjustments

`testbeam` was meant to be `multibeam`. the new testbench sets up data
using the time dimension as scanning angle to plot beam patterns. So
each time element is an angle. beamformer weights are ULA and the angles
chosen split up the number of beams. All the same data is in each
channel