Editing and deleting of markers. Also functionality of attaching additional note for the marker added.

Now markers can be **edit / delete** : 
 - We can attach additional note to each marker.
     - Note can be added to *popup* of that particular marker.
     - Just click on marker then put cursor in text area. After done with writing, click on ```save``` button.
     - Again we can edit and save this text content.

 - ```Delete marker``` button provided in marker popup to delete that marker.

 - Also on detail view of resource, we can *click on marker* to view attached note.