change scrollspy documentation to clarify javascript usage

* Port print styles from reset.less to scaffolding.less
* Port responsive image styles from reset.less to scaffolding.less

add comment regarding caveat of #6199 impl per discussion in/of 14844db8

Conflicts:
	less/bootstrap.less

Conflicts:
	docs/assets/css/bootstrap.css
	docs/templates/pages/base-css.mustache
	less/dropdowns.less
	less/forms.less

Merge branch 'dropdown-selectors' of https://github.com/blakeembrey/bootstrap into blakeembrey-dropdown-selectors

Conflicts:
	Makefile
	README.md
	component.json
	docs/assets/css/bootstrap-responsive.css
	docs/assets/css/bootstrap.css
	docs/assets/js/bootstrap-affix.js
	docs/assets/js/bootstrap-alert.js
	docs/assets/js/bootstrap-button.js
	docs/assets/js/bootstrap-carousel.js
	docs/assets/js/bootstrap-collapse.js
	docs/assets/js/bootstrap-dropdown.js
	docs/assets/js/bootstrap-modal.js
	docs/assets/js/bootstrap-popover.js
	docs/assets/js/bootstrap-scrollspy.js
	docs/assets/js/bootstrap-tab.js
	docs/assets/js/bootstrap-tooltip.js
	docs/assets/js/bootstrap-transition.js
	docs/assets/js/bootstrap-typeahead.js
	docs/assets/js/bootstrap.js
	docs/assets/js/bootstrap.min.js
	docs/index.html
	docs/templates/pages/base-css.mustache
	docs/templates/pages/index.mustache
	docs/templates/pages/javascript.mustache
	js/bootstrap-affix.js
	js/bootstrap-alert.js
	js/bootstrap-button.js
	js/bootstrap-carousel.js
	js/bootstrap-collapse.js
	js/bootstrap-dropdown.js
	js/bootstrap-modal.js
	js/bootstrap-...