[plotter] added fork for admin view

beat/web/plotters/admin.py

@@ -244,6 +244,7 @@ class PlotterParameterAdmin(admin.ModelAdmin):
                           'sharing',
                           'short_description',
                           'previous_version',
+                          'fork_of',
                          )
     search_fields      = ['author__username',
                           'name',
@@ -251,6 +252,8 @@ class PlotterParameterAdmin(admin.ModelAdmin):
                           'plotter__name',
                           'previous_version__author__username',
                           'previous_version__name',
+                          'fork_of__author__username',
+                          'fork_of__name',
                          ]
     list_display_links = ('id', 'name')
     list_filter        = ('sharing', )