Fix file system permissions for `normalize.css`

Close #1537.
Remove empty line from `main.js`

Close h5bp/html5-boilerplate#1538.
Update `CONTRIBUTING.md`

* Remove extra `the`.
* Remove IRC reference as it does not help the user in
  any way, plus, we don't have an official IRC channel.
Update to jQuery 1.11.1

See also: http://blog.jquery.com/2014/05/01/jquery-1-11-1-and-2-1-1-released/

Close h5bp/html5-boilerplate#1535.
Improve and update documentation: `TOC.md`

--

[✔] TOC.md
[ ] crossdomain.md
[ ] css.md
[ ] extend.md
[ ] faq.md
[ ] html.md
[ ] js.md
[ ] misc.md
[ ] usage.md

Cc: @drublic
Improve and update documentation: `crossdomain.md`

* Remove `crossdomain.md` and move its update content into `misc.md`.

--

[✔] TOC.md
[✔] crossdomain.md
[ ] css.md
[ ] extend.md
[ ] faq.md
[ ] html.md
[ ] js.md
[ ] misc.md
[ ] usage.md

Cc: @drublic
Improve and update documentation: `faq.md`

--

[✔] TOC.md
[✔] crossdomain.md
[ ] css.md
[ ] extend.md
[✔] faq.md
[ ] html.md
[ ] js.md
[ ] misc.md
[ ] usage.md

Cc: @drublic
Improve and update documentation: `css.md`

--

[✔] TOC.md
[✔] crossdomain.md
[✔] css.md
[ ] extend.md
[✔] faq.md
[ ] html.md
[ ] js.md
[ ] misc.md
[ ] usage.md

Cc: @drublic