Fix Python3 linting

doc/example-plugins/todo.py

@@ -1,3 +1,4 @@
+from __future__ import print_function
 import os
 import pickle
 
@@ -37,5 +38,5 @@ def process_message(data):
             num = int(text.split()[1]) - 1
             tasks[channel].pop(num)
         if text == "show":
-            print tasks
+            print(tasks)
         pickle.dump(tasks, open(FILE, "wb"))

rtmbot.py

@@ -210,7 +210,7 @@ if __name__ == "__main__":
                                                    directory
                                                    ))
 
-    config = yaml.load(file(args.config or 'rtmbot.conf', 'r'))
+    config = yaml.load(open(args.config or 'rtmbot.conf', 'r'))
     debug = config["DEBUG"]
     bot = RtmBot(config["SLACK_TOKEN"])
     site_plugins = []