Added system option to configure minimum password strength and length

install/tpl/system.ini.master

interface/lib/classes/validate_password.inc.php

interface/lib/lang/de.lng

interface/lib/lang/en.lng

interface/web/admin/form/remote_user.tform.php

interface/web/admin/form/system_config.tform.php

interface/web/admin/form/users.tform.php

interface/web/admin/lib/lang/de_system_config.lng

interface/web/admin/lib/lang/en_system_config.lng

interface/web/admin/templates/system_config_misc_edit.htm

interface/web/client/form/client.tform.php

interface/web/client/form/reseller.tform.php

interface/web/js/scrigo.js.php

interface/web/mail/form/mail_mailinglist.tform.php

interface/web/mail/form/mail_user.tform.php

interface/web/mailuser/form/mail_user_password.tform.php

interface/web/sites/form/database_user.tform.php

interface/web/sites/form/ftp_user.tform.php

interface/web/sites/form/shell_user.tform.php

interface/web/sites/form/web_domain.tform.php