Fix use before assignment bug with refresh token. Added more helpful logging.
 On branch master
 Changes to be committed:

	modified:   gspread/googoauth.py
Add multiple simultaneous user accounts.
 On branch master
 Your branch is ahead of 'origin/master' by 1 commit.

 Changes to be committed:

	modified:   test_gOAuth.py
	modified:   test_parms.py.example