Bugfix: Entrypoint created citext ext in wrong db

When using entrypoint-test.sh, the CITEXT extension ended up being
created in the regular mreg database, when it needs to be created in the
template1 database so it propagates to the temporary database created by
manage.py test.

entrypoint-test.sh

@@ -1,5 +1,5 @@
 #!/bin/sh
 set -e
 cd /app
-./manage.py create_citext_extension
+./manage.py create_citext_extension --database template1
 ./manage.py test --noinput --failfast

mreg/management/commands/create_citext_extension.py

@@ -1,17 +1,38 @@
 from django.core.management.base import BaseCommand, CommandError
 from django.db import connection
 from sys import stdout
+from django.conf import settings
+from psycopg2 import connect
 
 class Command(BaseCommand):
 	help = 'Create the CITEXT extension in the database.'
 
-	def handle(self, *args, **kwargs):
+	def add_arguments(self, parser):
+		# optional argument
+		parser.add_argument(
+			'--database',
+			type=str,
+			help='Database name',
+		)
+
+	def handle(self, *args, **options):
 		stdout.write("Attempting to create the CITEXT extension in the database...\n")
 		stdout.flush()
 		try:
-			with connection.cursor() as cursor:
+			con = connection
+			if options['database']:
+				stdout.write(f"Connecting to database {options['database']}\n")
+				stdout.flush()
+				con = connect(host=settings.DATABASES['default']['HOST'],
+					user=settings.DATABASES['default']['USER'],
+					password=settings.DATABASES['default']['PASSWORD'],
+					database=options['database'])
+			with con.cursor() as cursor:
 				cursor.execute("CREATE EXTENSION IF NOT EXISTS citext")
 				stdout.write(cursor.statusmessage+"\n")
 				stdout.flush()
+				con.commit()
 		except Exception as e:
+			stdout.write(e.__str__())
+			stdout.flush()
 			raise CommandError('Failed to create the CITEXT extension in the database.')