Particle Swarm Optimisation augmented

An augmentation of the popular implementation of PSO by Wesam Elshamy (submission 11559).

This is a version of Wesam Elshamy's PSO code that can be put to general use on any objective function. All parameters and hyper-parameters can be set at the command line by the user.

Functions that take matrix arguments (i.e. can compute objectives for the full swarm) are also supported, for efficiency.

Hopefully there is a place for this generalised version on the exchange: many thanks to Wesam Elshamy for the original code.