Store : avoid name collision

[Hartorn]

A test should be done on store creation to avoid name collision inside the store.
For example, it should not be possible to have two nodes named demande and errorDemande.

At the moment, it is problematic : the node errorDemande is created, but the data is dispatched as an error in demande

A solution would be to test if the array of node named prefixed by status, error has a non empty intersection with the array of node un prefixed