Give a state-less fashion for restclient api

[pfreixes]

Current resclient.Client api is none stateless, and it is usefull when we need to get more than one interaction with OpenAM server and the first one is one authentication call.

But we have to give a stateless fashion to make isolated queries using a token_id value got by the user.

One way to figure out that will use a new keyword at all public methods of Client class to give us the token value to be used.

c = restclient.Client(url, None, None, state_less = True)
c.logout(token_id="value")

Take care for current strong dependencie at Client init function with username, password and call straight for to authentication method. Here we are using a "patch" for avoid that with a new keyword called state_less.