GPII-742: Fix PCP's "Save & Apply" button behavior after user has logged out

Link to JIRA: http://issues.gpii.net/browse/GPII-742

You can see the issue coming up in the comments of http://issues.gpii.net/browse/GPII-540.

Temporarily to avoid the described logout-login issue, the "save" button gets disabled after logout and styled accordingly.