[#10,!3] version-get description clarified.

doc/api/version-get.json

 {
     "name": "version-get",
-    "brief": "The version-get command returns on the control channel what the
-              command line -v argument displays with in arguments the extended
-              version, i.e., what the command line -V argument displays.",
+    "brief": "The version-get command returns extended information about
+              Kea version. The returned string is the same as if Kea would
+              be run with -V command line option.",
     "description": "See <xref linkend=\"command-version-get\"/>",
     "support": [ "kea-dhcp4", "kea-dhcp6", "kea-ctrl-agent" ],
     "avail": "1.2.0",

doc/guide/ctrl-channel.xml

@@ -601,11 +601,10 @@ $ curl -X POST -H "Content-Type: application/json" -d '{ "command": "config-get"
       <section xml:id="command-version-get">
         <title>version-get</title>
         <para>
-          The <emphasis>version-get</emphasis> command returns on the control
-          channel what the command line <command>-v</command> argument
-          displays with in arguments the extended version, i.e., what
-          the command line <command>-V</command> argument displays. This command
-          does not take any parameters.
+          The <emphasis>version-get</emphasis> command returns an
+          extended information about Kea version. It is the same
+          information as Kea caled with <command>-V</command> command
+          line argument. This command does not take any parameters.
         </para>
 <screen>
 {