add softlayer installation instructions

Docker-DCO-1.1-Signed-off-by: Andrea Turli <andrea.turli@gmail.com> (github: andreaturli)

docs/sources/installation/index.rst

@@ -30,4 +30,5 @@ Contents:
    amazon
    rackspace
    google
+   softlayer
    binaries

docs/sources/installation/softlayer.rst

@@ -0,0 +1,27 @@
+:title: Installation on IBM SoftLayer 
+:description: Please note this project is currently under heavy development. It should not be used in production. 
+:keywords: IBM SoftLayer, virtualization, cloud, docker, documentation, installation
+
+IBM SoftLayer
+=============
+
+.. include:: install_header.inc
+
+There are several ways to install Docker on IBM SoftLayer, but probably the simplest way is the following:
+
+IBM SoftLayer QuickStart
+-------------------------
+
+1. Create an `IBM SoftLayer account <https://www.softlayer.com/cloudlayer/>`_.
+2. Log in to the `SoftLayer Console <https://control.softlayer.com/devices/>`_.
+3. Go to `Order Hourly Computing Instance <https://manage.softlayer.com/Sales/orderHourlyComputingInstance>`_ on your SoftLayer Console.
+4. Create a new CCI using the default values for all the fields and choose:
+
+- *First Available* as ``Datacenter`` and 
+- *Ubuntu Linux 12.04 LTS Precise Pangolin - Minimal Install (64 bit)* as ``Operating System``.
+
+5. Click the *Continue Your Order* button at the bottom right and select *Go to checkout*.
+6. Insert the required *User Metadata* and place the order.
+7. Then continue with the :ref:`ubuntu_linux` instructions.
+
+Continue with the :ref:`hello_world` example.