Various improvements.

Signed-off-by: Volker Theile <votdev@gmx.de>

installation/on_debian.rst

@@ -29,7 +29,7 @@ outlined below.
 On `Raspberry Pi OS <https://www.raspberrypi.org/software/operating-systems/>`_ the below
 instructions only partially work. Please refer to a specific `installation script <https://github.com/OpenMediaVault-Plugin-Developers/installScript>`_
 
-Install the openmediavault keyring manually::
+Install the |omv| keyring manually::
 
     apt-get install --yes gnupg
     wget -O "/etc/apt/trusted.gpg.d/openmediavault-archive-keyring.asc" https://packages.openmediavault.org/public/archive.key

installation/on_usb.rst

@@ -3,7 +3,7 @@ Installation on USB
 
 |omv| can be installed on an USB flash drive to boot from it.
 
-1. Follow the :doc:`Install on Dedicated Drive </installation/via_iso>`
+#. Follow the :doc:`Install on Dedicated Drive </installation/via_iso>`
    and select your USB flash drive as target drive.
-#. Enable the openmediavault-flashmemory plugin. This lowers the amount of
+#. Enable the ``openmediavault-flashmemory`` plugin. This lowers the amount of
    writes to the USB flash drive, making sure you can enjoy it for a long time.