Adding the 19 missions that were missing from Core French translation

[ilujito2]

All these changes are only related to French translation:

• Adding the 19 missions that were missing from Core Campaign French translation.
• Changes to the already available 13 Core Campaign missions, to have a uniform translation with the new files.
• Fixing couple wrong terms in ui translation file.
• Couple translation changes to 2 Fr tutorial mission files.