core: use new CKEditor name

FCK Editor is old name

https://ckeditor.com/old/forums/CKEditor-3.x/Should-FCKeditor-change-its-name

product/ERP5/bootstrap/erp5_core/SkinTemplateItem/portal_skins/erp5_core/Preference_getAvailableTextEditorList.py

-text_editor_list = [("Plain Text", "text_area"), ("FCK Editor", "fck_editor")]
+text_editor_list = [("Plain Text", "text_area"), ("CKEditor", "fck_editor")]
 
 if getattr(context.portal_skins, "erp5_code_mirror", None) is not None:
   text_editor_list.append(("Code Mirror", "codemirror"))

product/ERP5/bootstrap/erp5_core/SkinTemplateItem/portal_skins/erp5_core/Preference_viewHtmlStyle/my_preferred_text_editor.xml

@@ -222,7 +222,7 @@
                     <value>
                       <list>
                         <tuple>
-                          <string>FCK Editor</string>
+                          <string>CKEditor</string>
                           <string>fck_editor</string>
                         </tuple>
                         <tuple>

product/ERP5Form/EditorField.py

@@ -48,7 +48,7 @@ from zLOG import LOG
 class EditorWidget(Widget.TextAreaWidget):
   """
     A widget that displays a GUI HTML editor widget (based
-    on FCK editor). This widget is intended to be used in
+    on CKEditor). This widget is intended to be used in
     conjunction with WebSite.
     This Widget does not escape values.
 
@@ -70,7 +70,7 @@ class EditorWidget(Widget.TextAreaWidget):
                                    required=1,
                                    size=1,
                                    items=[('Standard Text Area', 'text_area'),
-                                          ('FCK Editor', 'fck_editor'),
+                                          ('CKEditor', 'fck_editor'),
                                           ('SVG Editor', 'svg_editor'),
                                           ('Spreadsheet Editor', 'spreadsheet_editor'),
                                           ('CodeMirror', 'codemirror')])