[#1990] docs about installing libyang and sysrepo

doc/sphinx/arm/install.rst

@@ -107,8 +107,10 @@ the system:
    This is specified using the --with-freeradius configuration switch.
 
 -  Sysrepo v1.4.140 and libyang v1.0.240 are needed to connect to a Sysrepo
-   datastore. This is specified using the --with-sysrepo option when running
+   datastore. Earlier versions are no longer supported. When compiling from
-   "configure". Earlier versions are no longer supported.
+   sources, the configure switches that can be used are --with-libyang and
+   --with-sysrepo without any parameters. If these dependencies were installed
+   in custom paths, point the switches to them.
 
 -  googletest (version 1.8 or later) is required when using the --with-gtest
    configuration option to build the unit tests.

doc/sphinx/arm/netconf.rst

@@ -17,23 +17,44 @@ Kea provides optional support for a YANG/NETCONF interface with the
 Installing NETCONF
 ==================
 
-To get its NETCONF capabilities, Kea uses Sysrepo.
+To get its NETCONF capabilities, Kea uses libyang v1.0.240 and sysrepo v1.4.140.
+Use packages if they are provided on your system. There is always the
+alternative method of building from sources which should work on all popular
+OSs:
 
-The following sections provide installation instructions for Ubuntu and CentOS.
+.. _libyang-install-sources:
 
-.. _netconf-ubuntu-install:
+Installing libyang From Sources
+-------------------------------
 
-Installing NETCONF on Ubuntu
+.. code-block:: console
-----------------------------
 
-For detailed installation instructions, see the `Ubuntu installation notes page <https://gitlab.isc.org/isc-projects/kea/wikis/docs/ubuntu-installation-notes>`__.
+    $ git clone https://github.com/CESNET/libyang.git
+    $ cd libyang
+    $ git checkout v1.0.240
+    $ mkdir build
+    $ cd build
+    $ cmake .. -DGEN_CPP_BINDINGS=ON -DGEN_LANGUAGE_BINDINGS=ON -DGEN_PYTHON_BINDINGS=OFF
+    $ make
+    $ make install  # without sudo if you're doing development and want to run unit tests
 
-.. _netconf-centos-install:
+.. _sysrepo-install-sources:
 
-Installing NETCONF on CentOS
+Installing sysrepo From Sources
-----------------------------
+-------------------------------
 
-For detailed installation instructions, see the `CentOS installation notes page <https://gitlab.isc.org/isc-projects/kea/wikis/docs/centos-installation-notes>`__.
+.. code-block:: console
+
+    $ git clone https://github.com/sysrepo/sysrepo.git
+    $ cd sysrepo
+    $ git checkout v1.4.140
+    $ mkdir build
+    $ cd build
+    $ cmake .. -DGEN_CPP_BINDINGS=ON -DGEN_LANGUAGE_BINDINGS=ON -DGEN_PYTHON_BINDINGS=OFF
+    $ make
+    $ make install  # without sudo if you're doing development and want to run unit tests
+
+.. _sysrepo-overview:
 
 Quick Sysrepo Overview
 ======================