Revert "Added configuration option to only allow OpenID logins."

This reverts commit 14b46e2183.

This functionality will need to be rewritten to work with the new
OpenIDPlugin.

Conflicts:

	index.php
	lib/logingroupnav.php

config.php.sample

@@ -38,8 +38,6 @@ $config['site']['path'] = 'laconica';
 // $config['site']['closed'] = true;
 // Only allow registration for people invited by another user
 // $config['site']['inviteonly'] = true;
-// Only allow registrations and logins through OpenID
-// $config['site']['openidonly'] = true;
 // Make the site invisible to  non-logged-in users
 // $config['site']['private'] = true;