This is similar to its WebGL and Android counterparts, we simply did not
have a version for desktop. This uses resgen to package the model's
textures (albedo, normal, roughness, metallic, ao) into a library that
is linked only to this sample.
This is a good test because it applies multiple textures to the model.
Moreover Aaron was asking me for a C++ example that uses compressed
textures.
For now this selects the OpenGL backend. We can change it to use Vulkan
after we add support for 3-band formats to VulkanDriver.
