Removed option to create "New <app_name>" from objects editor mode

* As issue reported to remove the option to add New file or any New Object from editing object page.
* Hence made the modification accordingly, various editing app templates to remove the add "file/object" option.

* Also given the app names on left side panel in list view templates. Used block  ```{% block meta_content %}``` to made all these modifications.

* For file list view given the name as ```Gallery``` on left side panel.
* Also given name ```Editor/<app_name> Editor``` on edit app templates for any app objects