add an interval parameter for better performance

[vincentfretin]

Add an interval parameter to specify a number of milliseconds to wait in between each intersection test, similar to what we have in A-Frame raycaster component. I set the default interval to 0 so there is no change in behavior.

With giant meshes like the ground generated with the environment component, when aiming with GearVR controller the fps drops from 60 to 30.
Specify interval: 100, I have 50 fps which is much better.

You can use aframe-fps-counter-component to see the fps in vr mode like this:

<a-entity id="cameraRig">
  <a-entity
    class="right-controller"
    gearvr-controls
    teleport-controls="cameraRig: #cameraRig; button: trigger; maxLength: 200; type: line; interval: 100; landingMaxAngle: 135; collisionEntities: .environmentGround, .environmentDressing"
  >
    <a-entity fps-counter="for90fps: false" position="0 0 -1" />
  </a-entity>
</a-entity>

[fernandojsg]

Cool, thanks!