Add script to turn players into meshes, ticks every 1 second

Trigger the player.lua file in init.lua

Commit the ugly and temporary test model and texture. We'll get to a real animated player mesh once the code for that is ready

Set visual_size accordingly so the player model doesn't stretch vertically (default of the sprite player)

Attempt to use the b3d model format, although it doesn't seem to work so far

mods/default/models/player.mtl

@@ -0,0 +1,12 @@
+# Blender MTL File: 'None'
+# Material Count: 1
+newmtl Material
+Ns 96.078431
+Ka 0.000000 0.000000 0.000000
+Kd 0.640000 0.640000 0.640000
+Ks 0.500000 0.500000 0.500000
+Ni 1.000000
+d 1.000000
+illum 2
+
+