Add AGPL Statement (#55)

README.md

@@ -110,12 +110,29 @@ follows:
 
 ## License
 
-FIWARE IoT Agent for LoRaWAN protocol is licensed under Affero General Public
-License (GPL) version 3.
+FIWARE IoT Agent for LoRaWAN protocol is licensed under [Affero General Public License (GPL)
+version 3](./LICENSE).
 
 © 2019 Atos Spain S.A
 
 The following third-party library is used under license:
 
 1. [iotagent-node-lib](https://github.com/telefonicaid/iotagent-node-lib) -
    **AGPL** © 2014-2019 Telefonica Investigación y Desarrollo
+
+### Are there any legal issues with AGPL 3.0? Is it safe for me to use?
+
+There is absolutely no problem in using a product licensed under AGPL 3.0. Issues with GPL 
+(or AGPL) licenses are mostly related with the fact that different people assign different 
+interpretations on the meaning of the term “derivate work” used in these licenses. Due to this,
+some people believe that there is a risk in just _using_ software under GPL or AGPL licenses
+(even without _modifying_ it).
+
+For the avoidance of doubt, the owners of this software licensed under an AGPL-3.0 license  
+wish to make a clarifying public statement as follows:
+
+> Please note that software derived as a result of modifying the source code of this
+> software in order to fix a bug or incorporate enhancements is considered a derivative 
+> work of the product. Software that merely uses or aggregates (i.e. links to) an otherwise 
+> unmodified version of existing software is not considered a derivative work, and therefore
+> it does not need to be released as under the same license, or even released as open source.