Notes:

"Parce que le crayon sera toujours au dessus de la barbarie! Parce que la liberté est un droit universal! Parce que vous nous soutenez! Nous, Charlie, sortirons votre journal mercredi prochain!

Charlie Hebdo, le journal des survivants; Mercredi 14/1"

Translation:
Because the pencil is always above barbarism! Because liberty is a universal right! Because you support us! We, Charlie, get out your newspaper next Wednesday!

Charlie Hebdo, the journal of the survivors; Wednesday 14/1 (14th of January)