Refactorisation of the creation poll service
This PR depends on the merge of !382 (merged)
The changes
The last confirmation step during poll creation flow is identical between date polls and classical polls.
- This PR moves the code in the
PollService
to be used in both creation poll controllers.
Other minor changes:
- MailService: expose a function
isEnabled
- SessionService: use a generic
removeAll
function to unset FORM data - cleanup: backport changes from date_poll into classic_poll