Warcraft 1 Structures (and other models/remakes...)

Modified version of the M3exporter.py that you would use with Blender. I modified 2 lines of code to change Calc_triangles to Calc_edges and Calc_edges_loose so you don't get that error in Blender 2.9. Just flop this in there with the rest of the old files and replace the old version of just this 1.