Update README.md

README.md

@@ -5,7 +5,7 @@ pyFDA
 [![PyPI version](https://badge.fury.io/py/pyfda.svg)](https://badge.fury.io/py/pyfda)
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 [![MIT licensed](https://img.shields.io/badge/license-MIT-blue.svg)](./LICENSE)
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+[![Google Group](https://img.shields.io/badge/Google%20Group-pyFDA-red.svg)](https://groups.google.com/forum/#!forum/pyfda)
 
 pyFDA is a GUI based tool in Python / Qt for analysing and designing discrete time filters. The capability for generating Verilog and VHDL code for the designed and quantized filters will be added in the next release.