doc fixes

Author: gonzalocasas

src/roslibpy/__init__.py

@@ -42,7 +42,7 @@
 =================
 
 ROS 1 vs ROS 2
-------------
+--------------
 
 This library has been tested to work with ROS 1. ROS 2 should work, but it is still
 in the works.

src/roslibpy/core.py

@@ -560,7 +560,7 @@ def send_goal(self, goal, resultback, feedback, errback):
         Note: The action client is non-blocking.
 
         Args:
-            request (:class:`.ServiceRequest`): Service request.
+            goal (:class:`.ActionGoal`): Action goal.
             resultback: Callback invoked on receiving action result.
             feedback: Callback invoked on receiving action feedback.
             errback: Callback invoked on error.