docs: proofreading of all the installation topics

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

docs/utils/filtron.sh.rst

@@ -7,9 +7,10 @@
 
 .. sidebar:: further reading
 
-   - :ref:`installation`
    - :ref:`searx filtron`
    - :ref:`architecture`
+   - :ref:`installation` (:ref:`nginx <installation nginx>` & :ref:`apache
+     <installation apache>`)
 
 .. _Go: https://golang.org/
 .. _filtron: https://github.com/asciimoo/filtron
@@ -77,31 +78,3 @@ The ``--help`` output of the script is largely self-explanatory
 (:ref:`toolboxing common`):
 
 .. program-output:: ../utils/filtron.sh --help
-
-.. _reverse proxy:
-
-Public Reverse Proxy
-====================
-
-To install searx in your public HTTP server use:
-
-.. code::  bash
-
-   sudo -H ./utils/filtron.sh apache install
-
-.. tabs::
-
-   .. group-tab:: apache
-
-      .. literalinclude:: ../../utils/templates/etc/apache2/sites-available/searx.conf:filtron
-	 :language: apache
-
-      .. tabs::
-
-	 .. group-tab:: Ubuntu / debian
-
-	       .. code-block:: sh
-
-		  $ sudo -H a2enmod headers
-		  $ sudo -H a2enmod proxy
-		  $ sudo -H a2enmod proxy_http