Prevent errors when saml authenticator is used along side of another authenticator.

For example basic/sample using an ldap auth for the basic part.
This was causing problems since this identifier was assuming a certain
	userid string and not forgiving when parsing it.
SAML Authenticate not recognizing sessioninfo during initial authentication.
Merge remote-tracking branch 'upstream/master'
Merge pull request #112 from richtera/master

In order to get SAML working I had to modify the sp plugin