-Texture renamed to Texture2D
-TextureLayered as base now inherits 2Darray, cubemap and cubemap array
-Removed all references to flags in textures (they will go in the shader)
-Texture3D gone for now (will come back later done properly)
-Create base rasterizer for RenderDevice, RasterizerRD
This allows more consistency in the manner we include core headers,
where previously there would be a mix of absolute, relative and
include path-dependent includes.
Added a dummy importer for textures to use with the server platform.
Allows for running a project in headless mode without crashing when loading scenes containing textured objects
Also as a result decreases load time as no image files have to be loaded.
