Update lock managet app

Add keyword arguments. Sort imports. Move settings and test
literals to their own module.

Signed-off-by: Roberto Rosario <Roberto.Rosario@mayan-edms.com>

mayan/apps/lock_manager/backends/file_lock.py

@@ -1,8 +1,8 @@
 from __future__ import unicode_literals
 
 import hashlib
-import logging
 import json
+import logging
 import os
 import threading
 import time
@@ -23,7 +23,9 @@ lock = threading.Lock()
 logger = logging.getLogger(__name__)
 
 lock_file = os.path.join(
-    setting_temporary_directory.value, hashlib.sha256(force_bytes(settings.SECRET_KEY)).hexdigest()
+    setting_temporary_directory.value, hashlib.sha256(
+        force_bytes(settings.SECRET_KEY)
+    ).hexdigest()
 )
 open(lock_file, 'a').close()
 logger.debug('lock_file: %s', lock_file)
@@ -76,7 +78,7 @@ class FileLock(LockingBackend):
             data = file_object.read()
 
             if data:
-                file_locks = json.loads(data)
+                file_locks = json.loads(s=data)
             else:
                 file_locks = {}
 
@@ -103,7 +105,7 @@ class FileLock(LockingBackend):
         with open(self.__class__.lock_file, 'r+') as file_object:
             locks.lock(f=file_object, flags=locks.LOCK_EX)
             try:
-                file_locks = json.loads(file_object.read())
+                file_locks = json.loads(s=file_object.read())
             except EOFError:
                 file_locks = {}