MTL reader cannot parse string value property

[chongkong]

Current implementation assumes every mtl property is either integer, float, or array of float. This prevents the parser from getting texture filename from map_Kd, map_Ks, etc.

wavefront_reader/wavefront_reader/reading.py

Lines 83 to 93 in c515164

	elif materials:
	if data:
	split_data = data.strip().split(' ')
	if len(split_data) > 1:
	material[prefix] = tuple(float(d) for d in split_data)
	else:
	try:
	material[prefix] = int(data)
	except ValueError:
	material[prefix] = float(data)

This should be fixed as

 elif materials: 
     if data: 
         split_data = data.strip().split(' ') 
  
         if len(split_data) > 1: 
             material[prefix] = tuple(float(d) for d in split_data) 
         else: 
             try: 
                 material[prefix] = int(data) 
             except ValueError:
                 try:
                     material[prefix] = float(data) 
                 except ValueError:
                     material[prefix] = data  # accept string value

This is also a direct solution to #1