Start CSV importer feature

config/locales/en.yml

@@ -49,6 +49,12 @@ en:
               invalid: "Allowed formats: xx:xx:xx, x:xx:xx, xx:xx, x:xx"
             puzzle_id:
               taken: "This contestant has already completed this puzzle"
+        csv_import:
+          attributes:
+            file:
+              blank: "No file selected"
+              empty: "This file is empty"
+              not_a_csv_file: "it must be a CSV file"
   completions:
     edit:
       title: "Edit completion"
@@ -75,6 +81,8 @@ en:
     edit:
       title: "Participant"
       team_title: "Teams"
+    import:
+      title: "Import participants from a CSV file"
     new:
       title: "New participant"
       team_title: "New team"
@@ -87,6 +95,7 @@ en:
     buttons:
       add: "Add"
       create: "Create"
+      import: "CSV Import"
       save: "Save"
   messages:
     convert: