Merge: Opportunity templates and pizzas

Adds templates to the Opportunity meetup creation page. The default software provides: 4 kinds of pizzas, 5 days work week and 7 days week. The software customized for xymus.net also provides: pizzas special LATECE and meeting hours for UQAM Sciences.

It is already available at http://xymus.net/opportunity/.

Pull-Request: #1539
Reviewed-by: Jean Privat <jean@pryen.org>
Reviewed-by: Lucas Bajolet <r4pass@hotmail.com>