Handle LDAP missing credentials error with a flash message.
Created by: patthoyts
If a user fails to provide a username or password to the LDAP login form then a 500 error is returned due to an exception being raised in omniauth-ldap. This gem has been amended to use the omniauth error propagation function (fail!) to pass this exception message to the registered omniauth failure handler so that the Rails application can handle it approriately.
The failure function now knows about standard exceptions and no longer requires a specific check for the OmniAuth::Error exception added by commit f322975.
This resolves issue #1077 (closed).
Signed-off-by: Pat Thoyts patthoyts@users.sourceforge.net