Move internal modules to “internal” folder.

.internal/baseEach.js

@@ -0,0 +1,14 @@
+import baseForOwn from './.internal/baseForOwn.js';
+import createBaseEach from './.internal/createBaseEach.js';
+
+/**
+ * The base implementation of `forEach`.
+ *
+ * @private
+ * @param {Array|Object} collection The collection to iterate over.
+ * @param {Function} iteratee The function invoked per iteration.
+ * @returns {Array|Object} Returns `collection`.
+ */
+const baseEach = createBaseEach(baseForOwn);
+
+export default baseEach;