fix: invalidate cache on comment deletion
Before, sqlites database-quote threw an error on the fixnum id. As we know that the id can only be a fixnum, we can just insert it without escaping, even if it hurts
throw possible entry errors
when an entry is empty (which can happen only by a prior bug), the blog should still not die
Introduce ajaxify option
cleaner code, building block for ham/spam-buttons ajaxification.
Hides unused undo-button for comments as well.
minor: TODO updated