* Update bundler-audit to version 0.5.0

* Update oj to version 3.0.6

* Update http-form_data to version 1.0.2

* Update parallel to version 1.11.2

* Update rails-i18n to version 5.0.4

* Update rack-protection to version 2.0.0

* Update haml to version 5.0.1

* Update scss_lint to version 0.53.0

* Relax requirement on i18n-tasks

* Remove haml and haml_lint gem requirement