function Collision(el, colliders, options) {
        this.options = $.extend(defaults, options);
        this.$element = el;
        this.last_colliders = [];
        this.last_colliders_coords = [];
        this.set_colliders(colliders);

        this.init();
    }
Detects collisions between a DOM element against other DOM elements or
Coords objects.

@class Collision
@uses Coords
@param {HTMLElement} el The jQuery wrapped HTMLElement.
@param {HTMLElement|Array} colliders Can be a jQuery collection
 of HTMLElements or an Array of Coords instances.
@param {Object} [options] An Object with all options you want to
       overwrite:
  @param {String} [options.overlapping_region] Determines when collision
   is valid, depending on the overlapped area. Values can be: 'N', 'S',
   'W', 'E', 'C' or 'all'. Default is 'C'.
  @param {Function} [options.on_overlap_start] Executes a function the first
   time each `collider ` is overlapped.
  @param {Function} [options.on_overlap_stop] Executes a function when a
   `collider` is no longer collided.
  @param {Function} [options.on_overlap] Executes a function when the
mouse is moved during the collision.
@return {Object} Collision instance.
@constructor