Main window: Rename menu 'edition' into 'edit'

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Update french translations

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Merge branch 'stable' into unstable

Conflicts:
	locale/fr.po
	locale/fr/LC_MESSAGES/paperwork.mo
	src/paperwork/frontend/mainwindow.glade

Signed-off-by: Jerome Flesch <jflesch@gmail.com>