Added redis pipeline, cmd arg for gui, register plugin

1. Used redis pipeline for consecutive writes when possible

2. Add --status_gui option for py.test. So, removed explicit plugin from self test as it creates conflict.

3. Register as plugin in setup.py using pytest11

4. Update todo

tests/test_plugin.py

@@ -2,7 +2,6 @@ import pytest_gui_status.status_plugin as status_plugin
 import subprocess
 from mock import patch
 import redis
-import pytest
 
 import os
 import tempfile
@@ -54,8 +53,6 @@ def test_whole_1(tmpdir):
     popen_pytest = subprocess.Popen(["py.test", "-s"], shell=True)
     popen_pytest.wait()
 
-    # pytest.main(["-s"])
-
     dir_name = os.getcwd()
     assert (dir_name == path_case)
     redis_db = redis.StrictRedis(host='localhost', port=REDIS_TEST_PORT, db=0)