Modal body shift fix for IE10/11

Closes #13103 by merging it.
bump grunt-saucelabs to v5.1.1
bump patch versions of 3 grunt tasks
Sauce tests: update iOS to v7.1
add document ready jQuery wrapper in Android Browser workaround
Merge pull request #13239 from twbs/doc-load-in-example

add document ready jQuery wrapper in Android Browser workaround
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`.