issue_140: switch to new CAS server
issue_140: use rubycas-client instead of rubycas-client-rails to reduce dependency because rubycas-client-rails is very old
issue_140: test disable forgery protection for single-sign-out, but does not seem to affect anything
issue_140: rubycas-client uses different filter than rubycas-client-rails
financial: issue 141
Merge branches 'issue_140' and 'financial' into production