Task #3: Integrate cmd_vel_mux ROS2 package

[VincentCadicamo]

Branch: feature/cmd-vel-mux

>>IMPORTANT<<

Make sure you are in a docker container when doing this task (Refer back to workshop 3)
Make sure you are working in the correct branch
Make sure your .gitignore file is correctly setup!!!! (Refer to workshop 2)
Make sure you branch off of the development branch
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I will update the description soon...