Fix tooltip viewport example

- Move example to correct location docs/examples/
- Move custom JS and CSS into stand-alone files
- Update headers and footers
- Copy-editing
Fix HTML errors
Add Gist & Customizer URLs to customized files & config.json

Fixes #9951
Fixes #12865
grunt dist
Merge pull request #13205 from twbs/fix-9951

Add Gist & Customizer URLs to customized files & config.json
Customizer: switch to UglifyJS2 (v2.4.13).

The uglify build is generated with `uglifyjs --self -o uglify.min.js`.
Add the jquery check in customizer's output.
Add the license header in the non minified build too.
Run `grunt`.