Add translations for active record models

Fix i18n spec

Add i18n activerecord files

Fix activerecord first name and last name labels

config/locales/activerecord.en.yml

@@ -0,0 +1,22 @@
+en:
+  activerecord:
+    models:
+      comment: Comment
+      debate: Debate
+      user: User
+      vote: Vote
+    attributes:
+      comment:
+        body: Comment
+        user: User
+      debate:
+        author: Author
+        description: Opinion
+        terms_of_service: Terms of service
+        title: Title
+      user:
+        email: Email
+        first_name: "First name"
+        last_name: "Last name"
+        nickname: Nickname
+        password: Password