docs(installing_deis): add deisctl version check

Author: Gabriel Monroy

docs/installing_deis/install-platform.rst

@@ -6,11 +6,18 @@
 Install the Deis Platform
 =========================
 
-.. important::
+We will use the ``deisctl`` utility to provision the Deis platform
+from a CoreOS host or a workstation that has SSH access to CoreOS.
 
-    Before installing the platform, please see :ref:`install_deisctl`.
+First check that you have ``deisctl`` installed and the version is correct.
+
+.. code-block:: console
+
+    $ deisctl --version
+    1.0.0
+
+If not, follow instructions to :ref:`install_deisctl`.
 
-From the computer you installed the Deis Control Utility, we will provision the Deis platform.
 Ensure your SSH agent is running and select the private key that corresponds to the SSH key added
 to your CoreOS nodes: