updated rails from 4.1.13 to 4.2.5. This is required for rails to make use of new features in postgres 9.5

@Ralf
TODO: migration /Users/groucho/Documents/HPI/workspace/Xikolo-CodeOcean/codeocean/db/migrate/20160204111716_add_user_to_code_harbor_link.rb
is broken. A reference is made to table users which does not exist.
Workaround: run rake db:schema:load before running db:migrate. Still this should be fixed.

config/locales/en.yml

@@ -1,3 +1,24 @@
+# Files in the config/locales directory are used for internationalization
+# and are automatically loaded by Rails. If you want to use locales other
+# than English, add the necessary files in this directory.
+#
+# To use the locales, use `I18n.t`:
+#
+#     I18n.t 'hello'
+#
+# In views, this is aliased to just `t`:
+#
+#     <%= t('hello') %>
+#
+# To use a different locale, set it with `I18n.locale`:
+#
+#     I18n.locale = :es
+#
+# This would use the information in config/locales/es.yml.
+#
+# To learn more, please read the Rails Internationalization guide
+# available at http://guides.rubyonrails.org/i18n.html.
+
 en:
   activerecord:
     attributes:
@@ -466,3 +487,4 @@ en:
     previous_label: '&#8592; Previous Page'
   file_template:
     no_template_label: "Empty File"
+