Add ranking mode

config/locales/en.yml

@@ -58,6 +58,7 @@ en:
         offline_form_description: Offline participants will have to fill the form by providing an image taken of the puzzle before starting solving it, and validate their finish time with an upload of an image of the completed puzzle
         offline_form_warning: Only for single-puzzle contests
         public: Enable the public scoreboard
+        ranking_mode: Ranking mode (public scoreboard & CSV exports)
         team: Team contest
         team_description: For UI display purposes mainly
         allow_registration: Allow registration
@@ -259,6 +260,10 @@ en:
     field: Field
     none: No field selected
     rank: Rank
+  lib:
+    ranking:
+      actual: First by time if completed, then by number of pieces assembled
+      theorical: By time only (projected time calculated with the ppm count)
   messages:
     index:
       no_messages: No messages received yet