[doc] improve documentation of make targets and ./manage script

BTW force modularization of the ./mange script into sub modules:

- utils/lib_sxng_data.sh
- utils/lib_sxng_node.sh
- utils/lib_sxng_static.sh
- utils/lib_sxng_test.sh
- utils/lib_sxng_themes.sh

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

docs/admin/buildhosts.rst

@@ -4,22 +4,30 @@
 Buildhosts
 ==========
 
-.. sidebar:: This article needs some work
-
-   If you have any contribution send us your :pull:`PR <../pulls>`, see
-   :ref:`how to contribute`.
-
 .. contents::
    :depth: 2
    :local:
    :backlinks: entry
 
-To get best results from build, it's recommend to install additional packages
-on build hosts (see :ref:`searxng.sh`).::
+To get best results from build, it's recommend to install additional packages on
+build hosts (see :ref:`searxng.sh`).
 
-  sudo -H ./utils/searxng.sh install buildhost
+.. _searxng.sh install buildhost:
 
-This will install packages needed by searx:
+Build and Development tools
+===========================
+
+To Install tools used by build and development tasks in once:
+
+.. tabs::
+
+  .. group-tab:: SearXNG's development tools
+
+     .. code:: sh
+
+        $ sudo -H ./utils/searxng.sh install buildhost
+
+This will install packages needed by SearXNG:
 
 .. kernel-include:: $DOCS_BUILD/includes/searxng.rst
    :start-after: START distro-packages
@@ -73,7 +81,7 @@ If your docs build (``make docs.html``) shows warnings like this::
             display), check the imgmath_latex setting
 
 you need to install additional packages on your build host, to get better HTML
-output.
+output (:ref:`install buildhost <searxng.sh install buildhost>`).
 
 .. tabs::
 
@@ -93,7 +101,7 @@ output.
 
       .. code-block:: sh
 
-         $ sudo dnf install graphviz graphviz-gd texlive-xetex-bin librsvg2-tools
+         $ sudo dnf install graphviz graphviz-gd ImageMagick texlive-xetex-bin librsvg2-tools
 
 
 For PDF output you also need:
@@ -117,9 +125,8 @@ For PDF output you also need:
       .. code:: sh
 
       	 $ sudo dnf install \
-	        texlive-collection-fontsrecommended texlive-collection-latex \
-		dejavu-sans-fonts dejavu-serif-fonts dejavu-sans-mono-fonts \
-		ImageMagick
+             texlive-collection-fontsrecommended texlive-collection-latex \
+             dejavu-sans-fonts dejavu-serif-fonts dejavu-sans-mono-fonts
 
 .. _sh lint:
 
@@ -128,7 +135,8 @@ Lint shell scripts
 
 .. _ShellCheck: https://github.com/koalaman/shellcheck
 
-To lint shell scripts, we use ShellCheck_ - a shell script static analysis tool.
+To lint shell scripts we use ShellCheck_ - a shell script static analysis tool
+(:ref:`install buildhost <searxng.sh install buildhost>`).
 
 .. SNIP sh lint requirements
 

docs/admin/settings/settings_redis.rst

@@ -24,20 +24,26 @@ developer) account needs to be added to the *searxng-redis* group.
     rediss://[[username]:[password]]@localhost:6379/0
     unix://[[username]:[password]]@/path/to/socket.sock?db=0
 
-.. admonition:: Tip for developers
+.. _Redis Developer Notes:
 
-   To set up a local redis instance, first set the socket path of the Redis DB
-   in your YAML setting:
+Redis Developer Notes
+=====================
 
-   .. code:: yaml
+To set up a local redis instance, first set the socket path of the Redis DB
+in your YAML setting:
 
-      redis:
-        url: unix:///usr/local/searxng-redis/run/redis.sock?db=0
+.. code:: yaml
 
-   Then use the following commands to install the redis instance ::
+   redis:
+     url: unix:///usr/local/searxng-redis/run/redis.sock?db=0
 
-     $ ./manage redis.build
-     $ sudo -H ./manage redis.install
-     $ sudo -H ./manage redis.addgrp "${USER}"
-     # don't forget to logout & login to get member of group
+Then use the following commands to install the redis instance (:ref:`manage
+redis.help`):
+
+.. code:: sh
+
+   $ ./manage redis.build
+   $ sudo -H ./manage redis.install
+   $ sudo -H ./manage redis.addgrp "${USER}"
+   # don't forget to logout & login to get member of group