Allow user to delete their own topic with no replies at any time

Unfortunately due to University-related commitments, i don’t have time to publish a multi-commit PR to establish safe hooks for a variety of time preferences. Furthermore, the hook i added to my self-hosted instance was much effort for an improvement that didn’t last long in a fast-moving core.

Therefore, at least for now, i’d recommend CDCK’s official hosting product and then emailing team@discourse.org to ask for the hard-coded value to be changed for the specific site involved.

Thanks