Opportunity

Intoducing Opportunity, a Meetup planifier (or planner, if we listen to @xymus, will correct that along with your remarks).

So, here's the long awaited Opportunity that will be the cornerstone of every ~~nutritious breakfast~~ Latece weekly seminar.

Maybe more once finished, let's conquer the world with Nit's amazing abilities for easy web development.

Also, a function was missing from SQLite, I needed it so, here it is as well.
Comment-ça nitcorn ne supporte pas le DELETE? Ses arguments devraient être dans `get_args`, mais ça n'a pas été testé.