Use short version of shorthand for margin declaration in 404.html

Closes #220.
Add `timeline` & `timelineEnd` in `plugins.js`

In Chrome and Opera the console object now includes two new methods:

 * `timeline`
    https://developer.chrome.com/devtools/docs/console-api#consoletimelinelabel

 * `timelineEnd`
    https://developer.chrome.com/devtools/docs/console-api#consoletimestamplabel

Close h5bp/mobile-boilerplate#221
Update to Apache Server Configs 2.7.1

Close h5bp/mobile-boilerplate#222
Add `Apache Server Configs` to `humans.txt`

Close h5bp/mobile-boilerplate#223
Add `lang=""` to `<html>`

Ref: https://github.com/h5bp/html5-boilerplate/commit/d916a720253d171a9b54818f2a07d14acbd2e4c7
Close: h5bp/mobile-boilerplate#224
Added `Normalize.css` in `humans.txt`

Close h5bp/mobile-boilerplate#225
Docs: Remove `tools` folder from file tree in usage.md

Close #226
Update to Apache Server Configs v2.8.0
Update `CHANGELOG.md`
Use `<!doctype html>` instead of `<!DOCTYPE html>`

Return back to the lowercase doctype in order to be more consistent
with the lowercase of the html tags.

Ref https://github.com/h5bp/html5-boilerplate/issues/1522
fixing conflicts