Sets up domain object models

Adds objective, adventure and narrative classes
[#76334086]

 Changes to be committed:
	new file:   app/assets/stylesheets/application.css.scss
	new file:   app/assets/stylesheets/bootstrap_and_customization.css.scss
	new file:   app/models/adventure.rb
	new file:   app/models/narrative.rb
	new file:   app/models/objective.rb
	renamed:    spec/models/adventures_spec.rb -> spec/models/adventure_spec.rb
	new file:   spec/models/narrative_spec.rb
	new file:   spec/models/objective_spec.rb