Align bare-metal-install-* docs with clr-installer verify-iso-integrity (#1186)

* Align bare-metal-install-* docs with clr-installer verify-iso-integrity

- New clr-installer feature, uses checksum to verify ISO image
- See also: https://github.com/clearlinux/clr-installer/pull/737
- Closes #1185
- Adds new section, Choose boot menu option.
- Figure 01 revised in bare-metal-desktop and -server
- Changes hierarchical levels of headers for consistency.
- Removes Software(optional) section from bare-metal-install-desktop
- Latter section is not relevant to installation process; no value
- Respond to reviewer feedback on wording.

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

* Wording revisions per reviewer feedback.

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

source/get-started/bare-metal-install-desktop.rst

@@ -37,6 +37,7 @@ Preliminary steps
 #. Follow your OS instructions to
    :ref:`create a bootable usb drive <bootable-usb>`.
 
+
 .. _install-on-target-start:
 
 Install from live image
@@ -61,28 +62,44 @@ these steps.
 
 .. _preliminary-steps-install-desktop-end:
 
-#. Select :guilabel:`Clear Linux OS` in the boot menu, shown in Figure 1.
+Choose boot menu option
+=======================
 
-   .. figure:: /_figures/bare-metal-install-desktop/bare-metal-install-desktop-01.png
-      :scale: 100%
-      :alt: Clear Linux OS in boot menu
+#. Choose one of the options shown in Figure 1.
 
-      Figure 1: Clear Linux OS in boot menu
+   a. Follow `Verify integrity of installer media (optional)`_.
+
+   #. Select :guilabel:`Clear Linux OS` in the boot menu.
+
+      .. figure:: /_figures/bare-metal-install-desktop/bare-metal-install-desktop-01.png
+         :scale: 100%
+         :alt: Clear Linux OS in boot menu
+
+         Figure 1: Clear Linux OS in boot menu
+
+      .. note::
+
+         If no action is taken, the live image starts by default.
 
 .. _install-on-target-end:
 
-Software (optional)
-===================
+Verify integrity of installer media (optional)
+==============================================
 
-Explore |CL| bundles and other software. Double-click the
-:guilabel:`Software` icon from the Activities menu, shown in Figure 2.
-Ensure a network connection exists before launching the Software application.
+Use :guilabel:`Verify ISO Integrity` to verify the checksum of 
+the image burned to the installer media. The checksum ensures that the ISO 
+is uncorrupted (see Figure 1). For every ISO generated, the 
+:guilabel:`clr-installer` implants checksums, which are verified during 
+early boot stage as part of :command:`initrd`. 
+ 
+#. Select :guilabel:`Verify ISO Integrity`. The media will be validated.
 
-.. note::
+#. If the check passes, it will boot into the live image. Continue in 
+   the next section.
 
-   While running the |CL| live desktop image, the Software application is
-   intended only for exploration. Do not attempt to install applications during
-   exploration.
+#. If the check fails, a failure message appears. 
+   
+   * Restart the process at `Preliminary Steps`_. 
 
 .. _install-clr-desktop-start:
 

source/get-started/bare-metal-install-server.rst

@@ -20,8 +20,8 @@ installation:
 * :ref:`system-requirements`
 * :ref:`compatibility-check`
 
-Download the latest |CL| live server image
-******************************************
+Preliminary steps
+*****************
 
 #. Visit our `Downloads`_ page.
 
@@ -62,7 +62,14 @@ Follow these steps to install |CL| on the target system:
 
 #. Reboot the target system.
 
-#. This action launches the |CL| installer boot menu, shown in Figure 1.
+Choose boot menu option
+=======================
+
+#. Choose one of the options shown in Figure 1.
+
+   a. Follow `Verify integrity of installer media (optional)`_.
+
+   #. Select :guilabel:`Clear Linux OS` in the boot menu.
 
    .. figure:: /_figures/bare-metal-install-server/bare-metal-install-server-01.png
       :scale: 100%
@@ -70,7 +77,27 @@ Follow these steps to install |CL| on the target system:
 
       Figure 1: Clear Linux OS Installer boot menu
 
-#. With :guilabel:`Clear Linux OS` highlighted, select :kbd:`Enter`.
+   .. note::
+
+      If no action is taken, the live image starts by default.
+
+Verify integrity of installer media (optional)
+==============================================
+
+Use :guilabel:`Verify ISO Integrity` to verify the checksum of 
+the image burned to the installer media. The checksum ensures that the ISO 
+is uncorrupted (see Figure 1). For every ISO generated, the 
+:guilabel:`clr-installer` implants checksums, which are verified during 
+early boot stage as part of :command:`initrd`. 
+ 
+#. Select :guilabel:`Verify ISO Integrity`. The media will be validated. 
+
+#. If the check passes, it will boot into the live image. Continue in 
+   the next section.
+
+#. If the check fails, a failure message appears. 
+   
+   * Restart the process at `Preliminary Steps`_. 
 
 .. _install-clr-server-start: