All promises should be handled

[Samuel-Therrien-Beslogic]

At the moment we have lots of promises marked with void , they should be handled at all time (.catch or .then with rejection handler).

All current .catch should be reviewed so that the error is best shown to the user depending on the context.

You can use the useErrorHandling to help get a string from messages. And use openAlertSnackbar to display it. Try to give the user as much info as possible. Strings comming from the backend or JS Exceptions don't need to be translated.