Add DARS v1 tutorial (#486)

* Add DARS getting started tutorial

* Update links to live DARS images

* updating link text in bash cmd

* Fix formatting & link ref

* Corrects sphinx directives; revises intro and other para for readability.

Signed-off-by: Michael Vincerra <michael.vincerra@intel.com>

source/clear-linux/tutorials/dars.rst

@@ -0,0 +1,102 @@
+.. _dars:
+
+Deep Analytics Reference Stack
+##############################
+
+This tutorial shows you how to use the Deep Analytics Reference Stack
+(DARS), and to optionally build your own images with the baseline Dockerfiles
+provided in the `DARS repository`_. Our tutorial assumes |CL-ATTR| is the
+host OS. However, any system that supports Docker containers can be used to
+follow these steps.
+
+.. contents::
+   :local:
+   :depth: 1
+
+The Deep Analytics Reference Stack release
+******************************************
+
+The Deep Analytics Reference Stack provides two prebuilt Docker images, available on `Docker Hub`_:
+
+* A Clear Linux derived `DARS with OpenBlas`_ stack optimized for `OpenBLAS`_
+* A Clear Linux derived  `DARS with MKL`_ stack optimized for `MKL`_
+
+You can get the latest component versions for each image in the
+:file:`README` found in the `DARS repository`_.  Because |CL| is a rolling
+distribution, the package version numbers in the |CL| based containers may
+not be the latest released by |CL|.
+
+Using the Docker Images
+***********************
+
+To immediately start using the latest stable DARS images, pull directly
+from `Docker Hub`_. For this tutorial we'll use the `Dars with MKL`_ version of the stack.
+
+Once you have downloaded the image, you can run it with
+
+.. code-block:: bash
+
+   docker run -it --ulimit nofile=1000000:1000000 --name mkl <name of image>
+
+This will launch the image and drop you into a bash shell inside the
+container.  You will see output similar to the following:
+
+.. code-block:: console
+
+   root@fd5155b89857 /root # spark-shell
+   spark-shell
+   Config directory: /usr/share/defaults/spark/
+   Welcome to
+     ____              __
+    / __/__  ___ _____/ /__
+    _\ \/ _ \/ _ `/ __/  '_/
+   /___/ .__/\_,_/_/ /_/\_\   version 2.4.0
+      /_/
+
+   Using Scala version 2.12.7 (OpenJDK 64-Bit Server VM, Java 1.8.0-internal)
+   Type in expressions to have them evaluated.
+   Type :help for more information.
+
+   scala>
+
+The :command:`--ulimit nofile` parameter is currently required in order to
+increase the number of open files opened at certain point by the spark
+engine.
+
+Building DARS Images
+********************
+
+If you choose to build your own DARS container images, you can customize
+them as needed. Use the provided Dockerfile as a baseline. To construct
+images with Clear Linux, start with a Clear Linux development platform that
+has the :command:`containers-basic-dev` bundle installed. Learn more about
+bundles and installing them by using :ref:`swupd-guide`.
+
+First, clone the `DARS repository`_ from GitHub.
+
+.. code-block:: bash
+
+   git clone https://github.com/clearlinux/dockerfiles/tree/master/stacks/dars -b master
+
+Then, inside the DARS directory, run :command:`make` to build OpenBLAS and
+MKL images, and run :command:`make baseline` to build the baseline CentOS
+image. Depending on the system, it may take a while to finish building.
+Once completed, check the resulting images with :command:`Docker`
+
+.. code-block:: bash
+
+   docker images | grep dars
+
+You can use any of the resulting images to launch fully functional
+containers.  If you need to customize the containers, you can edit the
+provided :file:`Dockerfile`.
+
+
+.. _DARS repository:  https://github.com/clearlinux/dockerfiles/tree/master/stacks/dars
+.. _Docker Hub: https://hub.docker.com/
+.. _OpenBLAS: http://www.openblas.net/
+.. _MKL: https://software.intel.com/en-us/mkl
+.. _CentOS: https://www.centos.org/
+.. _DARS with OpenBLAS: https://hub.docker.com/r/clearlinux/stacks-dars-openblas/
+.. _DARS with MKL: https://hub.docker.com/r/clearlinux/stacks-dars-mkl/
+.. _DARS on CentOS: https://hub.docker.com/r/clearlinux.......

source/clear-linux/tutorials/tutorials.rst

@@ -27,3 +27,4 @@ Explore our tutorials to discover what you can do with |CL|!
    dlrs/dlrs
    yubikey-u2f
    nvidia
+   dars