Fix sign in for OpenID enabled server.

The functional test Zanata server has OpenID and internal auth
enabled, which changes the login process. Basic internal
sign in still only available.
TODO: Tests for OpenID login.
(cherry picked from commit d62f98db687c961b6c46e7f03918cfaa0bba1240)

Conflicts:

	zanata-war/src/main/webapp/account/login.xhtml