Begin implementation of a "Space Explorer" tool

The purpose of this tool will be to visualise how search techniques of
complex optimisation spaces work in practise. This first commit contains
some of the bare-bones rigging to enable a variable-rate simulation with
start/stop/step controls.
se: Add WebGL space visualisation

This patch adds a terrain generator which is used to create simulated
"spaces", using three.js. It is based on the webgl terrain demo. See:

    http://threejs.org/examples/webgl_geometry_terrain.html