Optimize speed of turtlesim animation

With ipycanvas release 0.12.0, the draw_image function can draw
the turtles faster. This allows the animation to run more smoothly

Add ipycanvas dependency

Update installation instructions

README.md

@@ -30,10 +30,10 @@ on twitter: https://twitter.com/wuoulf, or join us on [Gitter](https://gitter.im
 ## Installation and Dependencies
 
 You need a ROS environment with rospy. We recommend using [Robostack](https://github.com/RoboStack/ros-noetic) (follow their installation instructions) which allows you to install ROS in a conda environment.
-Also required are `numpy` and `bqplot` for the live-plotting
-and `ipywidgets` for the interactive widgets
+Also required are `numpy` and `bqplot` for the live-plotting, 
+`ipywidgets` for the interactive widgets, and `ipycanvas` for the Turtlesim animations.
 
-    conda install jupyter bqplot pyyaml ipywidgets
+    conda install jupyter bqplot pyyaml ipywidgets ipycanvas
 
 `pyyaml` is necessary for rospy.
 

setup.py

@@ -92,7 +92,8 @@
         'ipywidgets>=7.0.0',
         'bqplot',
         'numpy',
-        'rospkg'
+        'rospkg',
+        'ipycanvas'
     ],
     'packages': find_packages(),
     'zip_safe': False,