add donate_core config to define enabled PaymentMethods
use the config to control which payment methods to display in front office
move some session handling code from PM to CoreBundle
add exception managment when an unknown payment method id is found in an intent
add PaymentBundle and CheckPromise plugin implementation
ajout de TODO sur les gestionnaires d'events
add recommandations
we now use a redirect to a checkpromise route to avoid duplicate intent on browser refresh
Manage Session expiration
add translations
Merge branch 'feature-checkpm' into devel