updates & addition in French

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@7931 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/resources/hudson/model/Computer/sidepanel_fr.properties

+Back\ to\ List=Retour à la liste
+Build\ History=Historique des builds

core/src/main/resources/hudson/model/ComputerSet/sidepanel_fr.properties

+Back\ to\ Dashboard=Retour au tableau de bord

core/src/main/resources/hudson/model/Slave/ComputerImpl/sidepanel_fr.properties

+Back\ to\ List=Retour à la liste
+Status=Statut
+Build\ History=Historique des builds
+Log=
+System\ Information=Information système
+Disconnect=Déconnection