This commit improve event.type (Event Categories) model and views in order
to ease event configuration through more detailed categories. The purpose
is to be able to define categories holding default data for website,
tickets, attendee mailing, ... Choosing a category on a new event takes
those default values to help users creating finely-tuned events.
Main configuration on event.type is
* auto confirmation, replacing the old system-wide auto confirmation
parameter
* seats limitation
* location: online events, timezone
* communication: reply-to email address, twitter hashtag, automated
mailing of attendees
* ticketing
* website parameters: display on website, display tracks, allow track
proposal
* question to attendees
Thibault Delavallée
91617bfc78