Attempted to make a list of words in word list display. Also, tried to give the list an input and submit control so that new words could be added to the list. This is heavily based on the "Add Some Control" tutorial we did for the pre-lab. Also, added a method to placeholder.js that displays the list length. Did this as one commit since it's all part of one item we're trying to make work.
Added tests for our listSize method. Made sure the new method is in both placeholder.js and wordlist.js. Fixed several typos in the method. Test passed.