Added german translation for file-in-use reference

This reverts commit 524df576.

Conflicts:
	inc/lang/bn/lang.php
	inc/lang/fr/lang.php

this has been done by a script and might not be 100% accurate

/ fix several typos / Fixes FS#2821

This reverts commit ba09710a.

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

When loading plugins, $lang might not be initialized yet, so use a
hardcoded error message instead, especially as this error should only be
displayed for the admin (and then fixed). This also removes the
previously localized message, it might be re-added as part of the new
extension manager.

This allows easier identifying of which version has been restored. (FS#2522)

Changing passwords might not be available.

This is in preparation for the new default template. This also updates the tpl_actiondropdown() to use most of them.

When autopasswd is disabled, the resend password option now asks for a
new password instead of autogenerating a new one and sending it by mail.

Note to translators: the wording for btn_resendpwd and resendpwd changed
to be more universal. English and German language files where updated -
other languages need to be adjusted.

Conflicts:

	inc/lang/en/lang.php