create basic functionality in postReducer

Author: vishalnagda1

src/reducers/postReducer.js

@@ -0,0 +1,13 @@
+import { FETCH_POSTS, NEW_POST } from "../actions/types";
+
+const initialState = {
+  items: [],
+  item: {},
+};
+
+export default function (state = initialState, action) {
+  switch (action.type) {
+    default:
+      return state;
+  }
+}