Updating library/bundle installation docs to use the new composer require (no version) functionality
Fixing bad link
Correct a typo.

Removed uncorrect "load use" phrase part, and replaced it with "you can
use", which I guess conveys the original meaning of the phrase better.
first import of the "Official Best Practices" book
Fixed some technical problems as suggested by Wouter
Added an index directive to the first chapter
updated fabpot/sphinx-php module reference
added the missing "best-practice" directive import in Sphinx configuration
Renamed "official best practices" to "best practices"
Fixed some typos reported by @henrikbjorn
Improve cookbook entry for error pages in 2.3~
[#4290] Re-adding version back
Re-adding one more version
Update http_cache.rst

Explained how the parameters are passed to the controller - named parameters
Clarifying a bit more that you're passing variables into your controller
Putting #pull-request-format anchor link back, which we link to in our contrib notes
Added config example for Varnish 4.0
Added Composer installation tip
[#4099] Adding an extra tip
[#4099] Trying to get the markup just right