adLDAP renamed the ad_username and ad_password to admin_username
admin_password recently. this makes our backend recognize the old
settings

again)

canDo getUsers to false when unavailable

This reverts commit ba09710a.

Conflicts:
	lib/plugins/authad/lang/de/settings.php

Before this fix the debug parameter always prevent the GIF from being
sent even though no actual debug information was returned unless the
allowdebug configuration option was set. Now the GIF is only disabled if
debugging is actually allowed.

de/de-informal: config plugin - Clean up the TOC in the configuration page / No need to add "Konfiguration" or "Plugin" to every element if the heading tells you that.

For just one image another syntax was used, this fixes the update script
to also fetch this image.

Without this unable to access AD info. Also allows SSO.

Wihtout this, unable to fetch any AD info.. also allows SSO.

jQuery 1.9.0 had a bug in replaceWith() that got fixed in 1.9.1 - to
ensure compatibility I upgraded the whole suite to their current
releases.