Merge pull request #309 from feuloren/master

Message pour l'exception NotEnoughtMoney
Remove assignation to unexistant variable
Log function arguments
Allow grouping stats by exact day, month or year
Merge pull request #310 from trecouvr/fix-user

Remove assignation to unexistant variable
Merge pull request #311 from trecouvr/log-args

Log function arguments
Merge pull request #312 from trecouvr/treso

Allow grouping stats by exact day, month or year
Mode maintenance (API Json uniquement)