allow require.resolve('bootstrap') to work under node
added 'main' field to package.json
added a separate npm-specific main file
Change value of stateful button after event loop

Fixes #14450
generate commonjs/npm entrypoint module via grunt task
Merge remote-tracking branch 'upstream/master' into node-requirable

Conflicts:
	Gruntfile.js
pulled output path out to gruntfile
code style fixes
added banner about generated file
code style improvement
Added link hover decoration variable
Allow to scroll the nav

Basically it's impossible to use the navigation if it's expanded. This will allow it to be scrollable so that the menus are accessable.
Fix #14856

[skip sauce]
Docs: Use a 180x180 apple-touch-icon.png.

Refs:
https://github.com/h5bp/html5-boilerplate/commit/1c4fcf32142e888946db579df0efbb52542e0ed1
https://github.com/h5bp/html5-boilerplate/commit/345925f04384b59929d8d39ba428cef548921408

[ci skip]
Update Jekyll to v2.4.0 and rouge to v1.7.2.
Update node dependencies.
grunt update-shrinkwrap

[skip sauce]
Merge pull request #14847 from twbs/node-deps

Update node dependencies.
Fixes #14799: Add vertical alignment of image in media component

Signed-off-by: Jenn Dodd <jedodd@pivotal.io>
Remove .media-object from docs.

Signed-off-by: Geoff Pleiss <gpleiss@pivotal.io>