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
Use e.target instead :focus selector.
Small clean-up in scrollspy unit test
Update normalize.css to v3.0.2.
Merge pull request #14743 from twbs/normalize-302

Update normalize.css to v3.0.2.
Change Twitter links to use `https`.
Merge pull request #14745 from twbs/twitter-https

Change Twitter links to use `https`.
Run `grunt`.
Update Blob.js to v2014-07-24.
Update FileSaver.js v2014-08-29.
Update less.js to v1.7.5.