Adding installation index

Signed-off-by: Mary Anthony <mary@docker.com>

docs/installation/index.md

@@ -0,0 +1,33 @@
+<!--[metadata]>
++++
+title = "Supported instllation"
+description = "Lists the installation methods"
+keywords = ["Docker install "]
++++
+<![end-metadata]-->
+
+# Supported installation
+
+Docker supports installation on the following: 
+
+* [Amazon EC2 Installation](amazon)
+* [Arch Linux](archlinux)
+* [Microsoft Azure platform](azure)
+* [Installation from binaries](binaries)
+* [CentOS](centos)
+* [CRUX Linux](cruxlinux)
+* [Debian](debian)
+* [Fedora](fedora)
+* [FrugalWare](frugalware)
+* [Gentoo](gentoolinux)
+* [Google Cloud Platform](google)
+* [Install on Joyent Public Cloud](joyent)
+* [Mac OS X](mac)
+* [Oracle Linux](oracle)
+* [Rackspace Cloud](rackspace)
+* [Red Hat Enterprise Linux](rhel)
+* [IBM SoftLayer](softlayer)
+* [openSUSE and SUSE Linux Enterprise](SUSE)
+* [Ubuntu ](ubuntulinux)
+* [Windows](windows)
+