Added status of development on README.md

README.md

@@ -5,14 +5,18 @@ A small class to interface with the NFC reader Module MFRC522 on the Raspberry P
 
 This is a Python port of the example code for the NFC module MF522-AN.
 
-##Requirements
+**Important notice:** This library has not being actively updated in almost four years.
+It might not work as intended on more recent Raspberry Pi devices. You might want to 
+take a look to the open pull-requests and forks to see other implementations and bug-fixes.
+
+# Requirements
 This code requires you to have SPI-Py installed from the following repository:
 https://github.com/lthiery/SPI-Py
 
-##Examples
+# Examples
 This repository includes a couple of examples showing how to read, write, and dump data from a chip. They are thoroughly commented, and should be easy to understand.
 
-## Pins
+#  Pins
 You can use [this](http://i.imgur.com/y7Fnvhq.png) image for reference.
 
 | Name | Pin # | Pin name   |
@@ -26,5 +30,8 @@ You can use [this](http://i.imgur.com/y7Fnvhq.png) image for reference.
 | RST  | 22    | GPIO25     |
 | 3.3V | 1     | 3V3        |
 
-##Usage
+# Usage
 Import the class by importing MFRC522 in the top of your script. For more info see the examples.
+
+# License
+This code and examples are licensed under the GNU Lesser General Public License 3.0.