Drop unused BaseIOBackend

It is not used by any other codes in the current repository.

Change-Id: Ief2074274176ce05279d1ef870ed14bd0d3238c3
Signed-off-by: Takashi Kajinami <kajinamit@oss.nttdata.com>

cloudkitty/backend/__init__.py

@@ -1,66 +0,0 @@
-# -*- coding: utf-8 -*-
-# Copyright 2014 Objectif Libre
-#
-#    Licensed under the Apache License, Version 2.0 (the "License"); you may
-#    not use this file except in compliance with the License. You may obtain
-#    a copy of the License at
-#
-#         http://www.apache.org/licenses/LICENSE-2.0
-#
-#    Unless required by applicable law or agreed to in writing, software
-#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
-#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
-#    License for the specific language governing permissions and limitations
-#    under the License.
-#
-import abc
-
-
-class BaseIOBackend(object, metaclass=abc.ABCMeta):
-    def __init__(self, path):
-        self.open(path)
-
-    @abc.abstractmethod
-    def open(self, path):
-        """Open the connection/file on the backend.
-
-        """
-
-    @abc.abstractmethod
-    def tell(self):
-        """Current position on the backend.
-
-        """
-
-    @abc.abstractmethod
-    def seek(self, offset, from_what=0):
-        # 0 beg, 1 cur, 2 end
-        """Change position in the backend.
-
-        """
-
-    @abc.abstractmethod
-    def flush(self):
-        """Force write informations on the backend.
-
-        """
-
-    @abc.abstractmethod
-    def write(self, data):
-        """Writer data on the backend.
-
-        :param data: Data to be written on the backend.
-        """
-
-    @abc.abstractmethod
-    def read(self):
-        """Read data from the backend.
-
-        :return str: Data read from the backend.
-        """
-
-    @abc.abstractmethod
-    def close(self):
-        """Close the connection/file on the backend.
-
-        """