let python sub processes use python3

hardware/neopixel/neopix.py

@@ -171,5 +171,5 @@ if __name__ == '__main__':
         except (EOFError, SystemExit):  # hopefully always caused by us sigint'ing the program
             sys.exit(0)
         except Exception as ex:
-            print "bad data: "+data
-            print ex
+            print("bad data: "+data)
+            print(ex)

hardware/neopixel/package.json

@@ -1,6 +1,6 @@
 {
     "name"          : "node-red-node-pi-neopixel",
-    "version"       : "0.0.19",
+    "version"       : "0.0.20",
     "description"   : "A Node-RED node to output to a neopixel (ws2812) string of LEDS from a Raspberry Pi.",
     "dependencies"  : {
     },