Resync develop to master

Closes #1988, #1480, #1431, #925, #1775, #1736, #1720, #1683, #1690, #1653, #1714, #1655, #1651, #1489, #1451, and #1472

See merge request !1195

fix(README.md): Fix some links in README.md

See merge request !1194

feat(doc): Canopsis 3.31.0 release notes and ChangeLog

See merge request !1192

feat(release): Release 3.31.0

See merge request !1187

Ajout de `leavemails` et `trim` dans la doc du connecteur `email2canopsis`

See merge request !1186

[Doc] Mise à jour de la documentation du connecteur zabbix2canopsis

See merge request !1181

chore(cleanup): Kill .travis.yml

See merge request !1172

feat(doc): Mention new canoctl options in Canopsis 3.31.0

See merge request !1182

Doc : précision des types d'événements qui créent des entités

See merge request !1183

Added the info that only check and declareticket create entities, also added the infos about declareticket and assocticket event types

Documentation part of #1960.

fix(i18n): Various French fixes in UI translations

See merge request !1031

Fix doc filter

See merge request !1168

fix(doc): Tell people that they shouldn't upgrade our dependencies with their own versions

See merge request !1175

Feature/Delete unused files

See merge request !1173

Seen with Julien.

Fixes #1988.

Just look at it and you'll understand how much broken it is.

fix(build): upgrade-self.sh was removed from build

See merge request !1171

Supprimé les mauvais champs et mis à jour le Snooze

See merge request !1167