Ad auth

Successfully tested against Active Directory to verify that the configuration works and both file based and AD based logins work.  The ldap configuration looks correct however I didn't test against a live ldap server.

Change includes logic to set the authentication flag to sufficient for all but the last method in the authentication configuration.  This allows each method to be tried and if fails it falls to the next method.

Switched the merge function to deep_merge for the auth_config to allow proper merging of nested hashes.