Fix welcome_fr.mkd to use proper French

Julien Kirch

2014-04-22 c90be0750bff761eb2f74bc16179d1f87304dfa4

 src/main/java/com/gitblit/manager/IUserManager.java

@@ -24,6 +24,7 @@
    *
    * @param username
    * @return true if the specified username represents an internal account
     * @since 1.4.0
    */
   boolean isInternalAccount(String username);