add licensing info of the project dependencies

LICENSE

@@ -1,3 +1,23 @@
+The source code of this project is licensed under the GNU Affero General
+Public License v3 (AGPLv3). The full text of this license is reproduced 
+at the end of this document.
+
+The project is using the following libraries and sdk:
+- mdebtls, licensed under Apache-2.0 and GPL-2.0-or-later licenses,
+  https://github.com/Mbed-TLS/mbedtls
+- tinyUSB, licensed under the MIT License,
+  https://github.com/hathach/tinyusb  
+- tinycbor, licensed under the MIT license,
+  https://github.com/intel/tinycbor
+- USB CCID from Raspberry Pi (Trading) Ltd, licensed under the BSD 
+  license, 
+- Raspberry Pi Pico SDK, licensed under BSD 3-Clause "New" or "Revised" 
+  License, https://github.com/raspberrypi/pico-sdk
+- Espressif IoT Development Framework (ESP-IDF), licensed under Apache License
+  Version 2.0, https://github.com/espressif/esp-idf
+
+________________________________________________________________________
+
                     GNU AFFERO GENERAL PUBLIC LICENSE
                        Version 3, 19 November 2007
 
@@ -658,4 +678,4 @@ specific requirements.
   You should also get your employer (if you work as a programmer) or school,
 if any, to sign a "copyright disclaimer" for the program, if necessary.
 For more information on this, and how to apply and follow the GNU AGPL, see
-<https://www.gnu.org/licenses/>.
+<https://www.gnu.org/licenses/>.