consolidate relatedTarget docs in dropdown event docs
Revert "Follow-up to #13074: use spec syntax instead of deprecated mixins"

This reverts commit b10b373c6019666dbe1152245c9efdf214ceaa6a.

Resolves #14937.
grunt
fix travis.yml lint errors
Merge pull request #15161 from twbs/travis-lint

fix travis.yml lint errors
add unit test for affix-top for padding issue
Fixes affix-top class not applying

Use scrollTop instead of colliderTop which uses the elements
offset().top, as the offset top does not account for padding.

This issue can be replicated by using a navbar-fixed-top and applying
relevant padding to the body. (A navbar-static-top with no padding on
the body does not encounter this issue)

Fixes #15078
Closes #15154 by merging it
Merge pull request #15154 from nickyod/affix-top-bug
Use npm instead NPM and update twbs team link.
Merge pull request #15166 from vsn4ik/upd_npm_and_core_team

Use npm instead NPM and update twbs team link.
grunt dist
Setup Travis event notification webhook for Savage
Merge pull request #15176 from twbs/savage-travis

Setup Travis event notification webhook for Savage
[skip sauce]
[skip validator]
enable Sauce access for Savage
skip HTML validator for Savage builds
disable core tests for Savage builds
grant Savage access to the S3 cache
Savage builds should not update the S3 cache
Merge pull request #15177 from twbs/savage-sauce

Adjust build scripts for Savage
Merge pull request #15090 from twbs/dropdowns-events

consolidate relatedTarget docs in dropdown event docs