For #194, convert the POTD management command to a celery task. Refactored to put the logic for the command into a function, and the command simply calls this function. The task can also just call this function. Added some basic tests for the new function.

"""Admin definitions for the antispam application."""

from django.contrib import admin

from antispam.models import SpamPhrase


class SpamPhraseAdmin(admin.ModelAdmin):
    search_fields = ('phrase', )


admin.site.register(SpamPhrase, SpamPhraseAdmin)