Adding missing installation page to docs

docs/documentation/installation/index.md

@@ -0,0 +1,58 @@
+---
+layout: default
+title: Installation - Documentation - sitespeed.io
+description: How to to install sitespeed.io. Use npm, our Vagrant files or Docker.
+keywords: installation, documentation, web performance, sitespeed.io
+author: Peter Hedenskog
+nav: documentation
+image: https://www.sitespeed.io/img/sitespeed-2.0-twitter.png
+twitterdescription: How to to install sitespeed.io. Use npm, our Vagrant files or Docker.
+---
+[Documentation]({{site.baseurl}}/documentation/) / Installation
+
+# Installation
+{:.no_toc}
+
+* Lets place the TOC here
+{:toc}
+
+
+## Docker
+
+We have [Docker images](https://hub.docker.com/u/sitespeedio/) with sitespeed.io, Chrome, Firefox and Xvfb. They are super easy to use (Xvfb is started automatically when you start the container). Here's how to use the container with both Firefox & Chrome (install [Docker](https://docs.docker.com/installation/ubuntulinux/) or [Docker toolbox](https://www.docker.com/toolbox) first and start them).
+
+~~~ bash
+$ sudo docker pull sitespeedio/sitespeed.io
+$ sudo docker run --privileged --rm -v "$(pwd)":/sitespeed.io sitespeedio/sitespeed.io sitespeed.io https://en.wikipedia.org/wiki/Barack_Obama -b firefox
+~~~
+
+That will output the data from the run in the current directory.
+
+
+# Download and installation
+
+## Install on Mac, Linux & Windows
+
+Prerequisites: Install [NodeJS](http://nodejs.org/download/) ([Linux](https://github.com/creationix/nvm)) and make sure you have [npm](https://github.com/npm/npm) installed.
+
+~~~ bash
+$ npm install sitespeed.io
+~~~
+
+If you want it installed globally (running it from wherever):
+
+~~~ bash
+$ npm install -g sitespeed.io
+~~~
+
+Run
+
+~~~ bash
+sitespeed.io -h
+~~~
+
+or on Windows:
+
+~~~ bash
+$ sitespeed.io.cmd -h
+~~~