Boids can access dynamic configuration

Some examples

```javascript
  /* Example 1 of Boid creation */
   w.new_boid( { colour: "green",
                 geo_data:  {
                               position: new Vector(220, 230),
                               velocity: new Vector(0, 0),
                               acceleration: new Vector(0, 0)
                            }
   })

```

```javascript
    var t = w.new_boid( function(config) {
                           /* Here you can interact with the outer scope */
                           config.colour   = "red"
                           config.geo_data = {
                              position: new Vector(200, 200),
                              velocity: new Vector(0, 0),
                              acceleration: new Vector(0, 0)
                           }
                           return config
    })

```

```javascript
    var ba = w.new_boid( {colour: "yellow"}, function(config) {
                           /* Here you can interact with the outer scope */
                           /* You can also access the already created brain */
                           alert("hey")
                           config.geo_data = {
                              position: new Vector(100, 100),
                              velocity: new Vector(0, 0),
                              acceleration: new Vector(0, 0)
                           }
                           return config
    })

```