Add a minimal README
# SensESP
-Universal Signal K sensor framework for ESP8266 and ESP32.
+
+SensESP is a Signal K sensor framework for ESP8266 and ESP32. At the moment it should be considered a proof of concept, heavily inspired by [SigkSens](https://github.com/mxtommy/SigkSens).
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+## Missing features
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+- [ ] Persistent configuration
+- [ ] HTTP control interface
+- [ ] Authentication token support
+- [ ] Implementation of individual hardware devices
