Data: don't store image data for a world.

AssetLoader: removed unused field __image_data from world handler.
World building; added Teleporter, alt Switch effect; Yellow=>Orange.

asset/world: semi-final a_bit_switchy, and I think start is done.

TODO: notes.

Data:
    replaced Color.Yellow with Color.Orange;
    added le crappis render_tile_inner_circle_abs() and
    render_tile_inner_circle().

Trigger/Switch: added trigger_switch_activate_2 sound and swappery.
Trigger/Teleporter: new trigger & sound.
Trigger/Message: keep existing state in reset().