use django.utils.dates.MONTHS_3 for short month names (resolves #225)
exclude KB from navigation if HELPDESK_KB_ENABLED is False (fixes #223)
Merge pull request #228 from brente/master

use django.utils.dates.MONTHS_3 for short month names
Merge pull request #230 from brente/navigation-nokb

exclude KB from navigation if HELPDESK_KB_ENABLED is False
Merge pull request #231 from brente/no-admin-url

Remove undocumented ADMIN_URL setting