document add-password

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
fix display string

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
update po

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
Merge branch 'gpaste-3.10'

* gpaste-3.10:
  update po
  fix display string
  document add-password