Moved/changed replace OBJ to ReplaceMesh.
Optional model/texture/material export.
Added Material export option, set shader and shader properties to assign exported textures.
Added Prefab export option, exports mesh as an Unity .asset file and creates a prefab to link it to the mesh filter/renderer, added the option for auto assignment of the exported material (New default).
Bugfix texture export: where textures regarding of their settings would be exported as sprites.
Update texture export: original textures will now be copied to get the pixel values with the correct import settings applied to prevent strange-looking normal maps and color changes.
Folder creation: the required folders will now be created by the tool, no need anymore to save empty folders.
Minor changes: Renamed some variables, testing a new layout error fix, started working on material export.
