Messages: fix federatedincomplete typo + phrasing

Fix "ammend" => "amend"

The text for
views.aaf.base.identity.federatedsessions.federatedincomplete.details
was also referring to the missing attributes as being highlighted, but
they are just listed in the alert frame.  Thus changing the phrasing
accordingly.
Messages: fix typo again

Embarassing...
Merge pull request #21 from University-of-Auckland/develop-fix-federatedincomplete-typos

Fix typos in the app-base message for incomplete federated login