fixed typo in exception

rhodecode/controllers/files.py

@@ -170,7 +170,7 b' class FilesController(BaseController):'
             return _('Unknown revision %s') % revision
         except EmptyRepositoryError:
             return _('Empty repository')
-        except (InproperArchiveTypeError, KeyError):
+        except (ImproperArchiveTypeError, KeyError):
             return _('Unknown archive type')
 
         response.content_type = content_type