FEATURE #1372: add feature for editing static pages.

User can edit static pages. The edit itself also stores history of changed columns.

modules/StaticPages/Resources/lang/en/admin.php

@@ -16,7 +16,7 @@ return [
     'successfullyCreated'    => 'Page successfully created',
     'noPagesAvailable'       => 'No static pages available. Try to create one first.',
     'viewPage'               => 'View page on web',
-    'edit'                   => 'Edit page',
+    'edit'                   => 'Edit page :name',
     'deletePage'             => 'Delete page (ireversible!)',
     'makePublic'             => 'Publish page',
     'makeProtected'          => 'Publish page only for logged users',
@@ -24,6 +24,8 @@ return [
     'invalidStatus'          => 'Cannot change status to something undefined.',
     'statusChanged'          => 'Status successfully changed.',
     'invalidPage'            => 'Specified page does not exist.',
-    'pageDeleted'            => 'Page :name (:url) successfully deleted.'
+    'pageDeleted'            => 'Page :name (:url) successfully deleted.',
+    'nothingToEdit'          => 'You did not submit any changes. Nothing was edited.',
+    'successfullyEdited'     => 'Edit successfull'
 
 ];