Don't explicitly reference global jQuery

Removes `window.jQuery` in favor of `jQuery`, fixes #10038
Bower: Ignore development and documentation files on bower.json. Fix #10313.

I've kept only the files I consider relevant to bower installation:

- Files in dist directory;
- Files in js directory;
- Files in less directory;
- bower.json file;
- README.md file;
- LICENSE file.
bower.json: Modify `assets` directory on ignore to `docs-assets`
added bower_components to .gitignore
Update README.md

Row 13 link update to tag v3.0.1
Merge pull request #11324 from boki-/patch-1

Update README.md
Use nesting for thumbnail styles
Update customizer.js
Merge pull request #11331 from xt0rted/patch-1

Update customizer.js
update version numbers in JS file comment headers to v3.0.1 & regrunt
& > == >
Merge pull request #11334 from glebm/patch-2

& > == >
don't use nonstandard window.location.origin in customizer JS; fixes #11317
Use nesting for .placeholder()
Merge pull request #11338 from ZDroid/nestform

Use nesting for .placeholder()
Fix #7398 in Basic template

See https://github.com/twbs/bootstrap/issues/7398#issuecomment-27617890 for details.
Thanks @martinburger
Merge pull request #11336 from twbs/fix-11317

don't use nonstandard window.location.origin in customizer JS
Removed duplicated class change from migration instructions
Merge pull request #11345 from pborreli/patch-3

Removed duplicated class change from migration instructions
Add toogle nav for screen readers in examples