gcoder.py reads only hte content of the file

Previously, gcoder.py read not only the content of the file, but also it's
filename. This could have led to unexpected exceptions.

gcoder.py

@@ -210,7 +210,7 @@ def main():
 		print "usage: %s filename.gcode" % sys.argv[0]
 		return
 
-	gcode = GCode(sys.argv[1])
+	gcode = GCode(list(open(sys.argv[1]))) 
 	
 	gcode.measure()
 
@@ -221,4 +221,4 @@ def main():
 	print "Filament used: %0.02fmm" % gcode.filament_length()
 
 if __name__ == '__main__':
-	main()
+	main()