Description of problem:

1) Pulp-admin supports logining from one user to another. If one makes several logins and at one point wants to know who is the owner of the session, it's not possible to do it. An option which is similar to 'whoami' in shell would be reasonable for pulp users, particularly, for administrators. 

2) There is no option to check the status of the granted certificate. One can only try to execute some pulp-admin command without -u/-p options or login every time. 


Expected results:
Some options similar to 'pulp-consumer status'

>> pulp-consumer status
This consumer is registered to the server
[localhost] with the ID [cheburahska].

>> pulp-admin status
Successfully logged in as [user]. Session certificate will expire at Oct  9 18:35:48 2015 GMT.

>> pulp-admin status
No active user