Fix double quoting of some messages in fr_FR and en translations

Translation messages usually follow the MessageFormat convention, double-quoting quotes (see http://docs.oracle.com/javase/7/docs/api/java/text/MessageFormat.html), only if there are parameters. Other messages do not need double quotes.

Need to fix some translation messages, not following this convention, and need to make sure that the following labels displayed in the admin center will not need to be double quoted:

label.studio.update.status.noStatus=pas d''installation pr\u00e9c\u00e9dente.
label.studio.update.validation.error=Le syst\u00e8me a d\u00e9tect\u00e9 une incoh\u00e9rence \
sur la plate-forme cible ou sur l''une de ses d\u00e9pendances. V\u00e9rifiez la configuration \
de votre projet Studio et de ce serveur.

Also, messages from lang-ext (imported via Crowdin) do not follow this convention correctly, see NXP-14376.