Show all the names in the list
When the "Show Names" button (below) is clicked, output all of the names in
                nameList
                to the #output_container div element below. Tips:
            
- Make a function called showNames()
- In that function, make a "for loop" that repeats 20 (nameList.length) times
- Inside the body of the "for loop", target the #output_container element and append a paragraph (p tag) holding the name of the student.
- Don't forget to attach the function to the button's click event handler.
- Implement the "Clear" button too.