euscanwww: Watched herds/maintainers/categories panel

* Refactored templates and templatetags
* Added unfavourite views
* Added button to favourite/unfavourite package
* Panel for showing favourited objects

Signed-off-by: volpino <fox91@anche.no>

euscanwww/djeuscan/templates/euscan/_package_cols.html

@@ -1,4 +1,4 @@
-{% load packages %}
+{% load euscan %}
 {% load mul %}
 {% load sub %}
 {% load div %}