Use nothing-changed helper in home to prevent unnecessary render

lib/notifications.js

@@ -5,6 +5,7 @@ import Moment from 'moment'
 import { settings as labels } from '../components/labels'
 import { getOrCreateCycleDay, getBleedingDaysSortedByDate } from '../db'
 import cycleModule from './cycle'
+import nothingChanged from '../helpers/db-unchanged'
 
 export default function setupNotifications(navigate) {
   Notification.configure({
@@ -80,7 +81,3 @@ function setupPeriodReminder() {
     }
   }
 }
-
-function nothingChanged(dbChanges) {
-  return Object.values(dbChanges).every(changeArray => changeArray.length === 0)
-}