Eliminate empty word at end of top words list.

www/wordlist/wordlist.js

@@ -13,7 +13,7 @@ const dictionaryPromise = fetch('../wordlist/dictionaries/en_US/en_US.aff')
 const topWordsPromise = fetch('../wordlist/en_50k.txt')
     .then(response => response.text())
     .then(text => {
-        topWords = text.split('\n').map(line => {
+        topWords = text.trim().split('\n').map(line => {
             var arr = line.split(' ');
             return {'word': arr[0], 'frequency': Number(arr[1])};
         });