move base template outside of theme file and fix lint errors

peers/admin.py

peers/models.py

poller/urls.py

poller/views.py

templates/403.html

templates/404.html

templates/apply.html

templates/b3theme/base.html

templates/base.html

templates/dashboard.html

templates/error.html

templates/flatpages/default.html

templates/overview/index.html

templates/overview/login.html

templates/profile.html

templates/registration/activate.html

templates/registration/activate_edit.html

templates/registration/activation_complete.html

templates/registration/select_institution.html

templates/user_routes.html