Fixed #14356. Remove some dead imports from django.core.management.sql. Thanks…

Fixed #14356.  Remove some dead imports from django.core.management.sql.  Thanks to xiaket for the report and patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@14088 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/core/management/sql.py

@@ -2,12 +2,9 @@ import os
 import re
 
 from django.conf import settings
-from django.contrib.contenttypes import generic
 from django.core.management.base import CommandError
-from django.dispatch import dispatcher
 from django.db import models
 from django.db.models import get_models
-from django.db.backends.util import truncate_name
 
 def sql_create(app, style, connection):
     "Returns a list of the CREATE TABLE SQL statements for the given app."