Refactor build info, refactor dtu-core configuration

.gitlab-ci.yml

README.md

SYNTHETIC_TEST.md

app/assets/stylesheets/headers.scss

app/helpers/application_helper.rb

app/models/deployment_info.rb

app/views/shared/_course_header.html.erb

app/views/shared/_quiz_info.html.erb

config/application.rb

config/build_info.yml

config/initializers/deployment-info.rb

config/routes.rb

deps/dtu-core

scripts/gen-build-info.sh

scripts/localrails.sh

scripts/run-tests.sh

spec/rails_helper.rb