SMTPAccountStatusNotificationHandler: Subject should allow tokens as well + token tweaking

SMTPAccountStatusNotificationHandler should allow in subject the usage of same tokens as in the message template. Furthermore tokens should allow simple options to tweak the result of the replacement.

The attached patch accomplish this. It allows %%TOKEN

{options}

%% whereby options is a simple string, which gets processed by the corresponding *NotificationMessageTemplateElement. Usually it honors 'u'||'l' for converting the token replacement result into upper|lower case, allow to specify separator strings for multi-valued results, and index lists for userDNs (for more info see API docs).