🔥 Remove the post-trip-prompt code

This includes both copies (incident and survey)

Testing done:
- No instances left

```
$ grep -ri posttrip.prompt www/js
$ grep -ri PostTripAutoPrompt www/js
$
```

- UI loaded without errors

www/index.html

@@ -94,7 +94,6 @@
     <script src="js/survey/one-click-button.js"></script>
     <script src="js/incident/post-trip-manual.js"></script>
     <script src="js/survey/multilabel/infinite_scroll_filters.js"></script>
-    <script src="js/survey/multilabel/post-trip-prompt.js"></script>
     <script src="js/survey/multilabel/post-trip-map-display.js"></script>
     <script src="js/survey/multilabel/trip-confirm-services.js"></script>
     <script src="js/survey/multilabel/multi-label-ui.js"></script>

www/js/controllers.js

@@ -6,16 +6,15 @@ angular.module('emission.controllers', ['emission.splash.updatecheck',
                                         'emission.splash.storedevicesettings',
                                         'emission.splash.localnotify',
                                         'emission.splash.remotenotify',
-                                        'emission.stats.clientstats',
-                                        'emission.survey.multilabel.posttrip.prompt'])
+                                        'emission.stats.clientstats'])
 
 .controller('RootCtrl', function($scope) {})
 
 .controller('DashCtrl', function($scope) {})
 
 .controller('SplashCtrl', function($scope, $state, $interval, $rootScope, 
     UpdateCheck, StartPrefs, PushNotify, StoreDeviceSettings,
-    LocalNotify, RemoteNotify, ClientStats, PostTripAutoPrompt)  {
+    LocalNotify, RemoteNotify, ClientStats)  {
   console.log('SplashCtrl invoked');
   // alert("attach debugger!");
   // PushNotify.startupInit();