Fix up review comments in the packaging aspects of the program.

Signed-off-by: Chris Lalancette <[email protected]>

Author: clalancette

image_tools_py/package.xml

@@ -9,11 +9,13 @@
 
   <build_depend>rclpy</build_depend>
 
-  <exec_depend>rclpy</exec_depend>
-  <exec_depend>std_msgs</exec_depend>
   <!-- Note that this is only a symbolic dependency on python3-opencv3:
-       it won't actually be resolved by rosdep as the rosdep key does not currently exist -->
+       it won't actually be resolved by rosdep as the rosdep key (and for that matter,
+       the package itself) does not currently exist -->
   <exec_depend>python3-opencv3</exec_depend>
+  <exec_depend>rclpy</exec_depend>
+  <exec_depend>std_msgs</exec_depend>
+  <exec_depend>sensor_msgs</exec_depend>
 
   <!-- These test dependencies are optional
   Their purpose is to make sure that the code passes the linters -->

image_tools_py/setup.py

@@ -10,7 +10,6 @@
         'src.showimage_py',
     ],
     install_requires=[
-        'launch',
         'setuptools',
     ],
     keywords=['ROS'],