Turns on 3D viewing only for the constructions that use a 3D primitive, but loads the more extensive web3d bundle from the embedded GeoGebra package whenever any applet on the page uses 3d. (The idea is to only require the loading of one bundle per page.) Provides progress on #36.
Reviewed-on: #40
Co-authored-by: Glen Whitney <glen@studioinfinity.org>
Co-committed-by: Glen Whitney <glen@studioinfinity.org>
