[+] Added derective pragma once and header license GPL V3.

include/dap_chain_plugins_command.h

+#pragma once
+/*
+* Authors:
+* Alexey V. Stratulat <alexey.stratulat@demlabs.net>
+* DeM Labs Inc.   https://demlabs.net
+* DeM Labs Open source community https://gitlab.demlabs.net/cellframe/libdap-plugins-python
+* Copyright  (c) 2017-2020
+* All rights reserved.
+
+This file is part of DAP (Deus Applications Prototypes) the open source project
+
+   DAP (Deus Applicaions Prototypes) is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   DAP is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with any DAP based project.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
 #include "dap_chain_node_cli.h"
 #include "dap_chain_node_cli_cmd.h"
 #include "dap_chain_plugins_manifest.h"