French language corrections and additions.

Added missing french entries and corrected ones in spelling, accuracy and formalism.

As for "navigation" vs "cartographie", basically "cartographie" is map drawing, while navigation is actual use of the map to orient yourself.

To whoever whom would be tempted to write nord with a capital ;-)
http://fr.wikipedia.org/wiki/Usage_des_majuscules_en_fran%C3%A7ais#Points_cardinaux