merge dev branch (more tests) (#47)

* more tests and bugfixes on spells

* linting

functions/CountOccurences.js

@@ -1,5 +1,3 @@
-const CountOccurences = (arr, value) => {
-    return arr.filter(v => v === value).length;
-};
+const CountOccurences = (arr, value) => arr.filter(v => v === value).length;
 
 module.exports = { CountOccurences };