Missing iteratee call in groupBy and keyBy.

groupBy.js

@@ -23,6 +23,7 @@ const hasOwnProperty = Object.prototype.hasOwnProperty
  */
 function groupBy(collection, iteratee) {
   return reduce(collection, (result, value, key) => {
+    key = iteratee(value)
     if (hasOwnProperty.call(result, key)) {
       result[key].push(value)
     } else {

keyBy.js

@@ -25,7 +25,7 @@ import reduce from './reduce.js'
  */
 function keyBy(collection, iteratee) {
   return reduce(collection, (result, value, key) => (
-    baseAssignValue(result, key, value), result
+    baseAssignValue(result, iteratee(value), value), result
   ), {})
 }