BK-2085 Remove redundant command

Author: ride90

lib/booktype/apps/importer/management/__init__.py

@@ -34,7 +34,7 @@ def add_arguments(self, parser):
                             action='store',
                             dest='output_name',
                             default=None,
-                            help='Output filename or -- for STDOUT, e.g. my_book.zip.')
+                            help='Output filename or -- for STDOUT, e.g. my_book.epub.')
 
     def handle(self, *args, **options):
         book_name = options['<book name>'][0]