Add a switch for enabling the placement

[MAILPOET-3075]

views/form/editor.html

@@ -41,6 +41,7 @@
 <% block translations %>
 <%= localize({
   'displayForm': __('Display the form'),
+  'enable': __('Enable'),
   'addFormName': _x('Add form name', 'A placeholder for form name input'),
   'changesNotSaved': __('Your changes you made may not be saved'),
   'back': __('Back'),