Localize the step options and the model attribute names

The settings page rendered "15 min" with hard-coded English, and
IssueDatetime validation messages fell back to raw attribute names in
every locale. Both now come from the locale files, EN and JA (#18).

Author: dkastl

app/views/settings/_redmine_issue_datetime.html.erb

@@ -12,8 +12,10 @@
 <p>
   <label><%= l(:label_issue_datetime_step) %></label>
   <%= select_tag 'settings[time_step]',
-                 options_for_select([5, 10, 15, 30, 60].map { |m| ["#{m} min", m.to_s] },
-                                    RedmineIssueDatetime.settings['time_step']) %>
+                 options_for_select(
+                   [5, 10, 15, 30, 60].map { |m| [l(:label_issue_datetime_step_minutes, count: m), m.to_s] },
+                   RedmineIssueDatetime.settings['time_step']
+                 ) %>
 </p>
 <p>
   <label><%= l(:label_issue_datetime_zone) %></label>

config/locales/en.yml

@@ -1,11 +1,17 @@
 en:
+  activerecord:
+    attributes:
+      issue_datetime:
+        starts_at: Start time
+        ends_at: Due time
   field_start_time: Start time
   field_due_time: Due time
   field_all_day: All day
   label_datetime: Date and time
   text_datetime_cf_zone_hint: "Values are entered and shown in %{zone}, the reference time zone configured for this plugin."
   label_issue_datetime_trackers: Enabled for trackers
   label_issue_datetime_step: Time input step
+  label_issue_datetime_step_minutes: "%{count} min"
   label_issue_datetime_zone: Reference time zone
   label_issue_datetime_zone_default: Application default
   text_issue_datetime_zone_hint: Used to derive the date part mirrored into the start and due date fields.

config/locales/ja.yml

@@ -1,11 +1,17 @@
 ja:
+  activerecord:
+    attributes:
+      issue_datetime:
+        starts_at: 開始時刻
+        ends_at: 期日時刻
   field_start_time: 開始時刻
   field_due_time: 期日時刻
   field_all_day: 終日
   label_datetime: 日付と時刻
   text_datetime_cf_zone_hint: "値はこのプラグインで設定した基準タイムゾーン %{zone} で入力・表示されます。"
   label_issue_datetime_trackers: 有効にするトラッカー
   label_issue_datetime_step: 時刻入力の間隔
+  label_issue_datetime_step_minutes: "%{count}分"
   label_issue_datetime_zone: 基準タイムゾーン
   label_issue_datetime_zone_default: アプリケーションのデフォルト
   text_issue_datetime_zone_hint: 開始日・期日に反映する日付の算出に使用します。