[GH-24]Revert auto_commit=True for compatability (#25)

In v0.3.0, auto_commit=False is set as default, this is incompatible
with previous behavior, this change revert to auto_commit=True to
avoid any confusion.

fixes #24

persistqueue/sqlbase.py

@@ -52,7 +52,7 @@ class SQLiteBase(object):
     _MEMORY = ':memory:'  # flag indicating store DB in memory
 
     def __init__(self, path, name='default', multithreading=False,
-                 timeout=10.0, auto_commit=False):
+                 timeout=10.0, auto_commit=True):
         """Initiate a queue in sqlite3 or memory.
 
         :param path: path for storing DB file.
@@ -62,7 +62,10 @@ def __init__(self, path, name='default', multithreading=False,
                                one for **put** and one for **get**.
         :param timeout: timeout in second waiting for the database lock.
         :param auto_commit: Set to True, if commit is required on every
-                            INSERT/UPDATE action.
+                            INSERT/UPDATE action, otherwise False, whereas
+                            a **task_done** is required to persist changes
+                            after **put**.
+
 
         """
         self.memory_sql = False