Merge pull request #33 from gitter-badger/gitter-badge

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README.md

 # Arduino-Pico
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+[![Join the chat at https://gitter.im/arduino-pico/community](https://badges.gitter.im/arduino-pico/community.svg)](https://gitter.im/arduino-pico/community?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
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 Raspberry Pi Pico Arduino core, for all RP2040 boards
 
 This is a port of the RP2040 (Raspberry Pi Pico processor) to the Arduino ecosystem.