implemented redux for state management

src/store/reducers/reducerDocumentary.js

@@ -0,0 +1,11 @@
+import { FETCH_DOCUMENTARIES } from '../actions/index';
+
+export default function (state = {}, action) {
+  switch (action.type) {
+    case FETCH_DOCUMENTARIES:
+      const data = action.payload.data.results;
+      return { ...state, data }
+    default:
+      return state;
+  }
+}