Refactor - moved SFTP handle and attributes classes.

Added binding to SFTP directives for contextmanager.
Updated SFTP read and readdir functions to return size/error code along with data.
Updated tests to use setUpClass and for moved sftp modules.

Author: Pan

embedded_server/openssh.py

@@ -28,6 +28,7 @@
     [DIR_NAME, 'sshd_config.tmpl']))
 SSHD_CONFIG = os.path.abspath(os.path.sep.join([DIR_NAME, 'sshd_config']))
 
+
 class OpenSSHServer(object):
 
     def __init__(self, port=2222):