Added notice to README.md about the new default branch

README.md

@@ -4,14 +4,18 @@ ESPurna ("spark" in Catalan) is a custom firmware for ESP8266 based smart switch
 It uses the Arduino Core for ESP8266 framework and a number of 3rd party libraries.
 
 [![version](https://img.shields.io/badge/version-1.12.4-brightgreen.svg)](CHANGELOG.md)
-![branch](https://img.shields.io/badge/branch-dev-orange.svg)
-[![travis](https://travis-ci.org/xoseperez/espurna.svg?branch=dev)](https://travis-ci.org/xoseperez/espurna)
-[![codacy](https://img.shields.io/codacy/grade/c9496e25cf07434cba786b462cb15f49/dev.svg)](https://www.codacy.com/app/xoseperez/espurna/dashboard)
+![branch](https://img.shields.io/badge/branch-master-orange.svg)
+[![travis](https://travis-ci.org/xoseperez/espurna.svg?branch=master)](https://travis-ci.org/xoseperez/espurna)
+[![codacy](https://img.shields.io/codacy/grade/c9496e25cf07434cba786b462cb15f49/master.svg)](https://www.codacy.com/app/xoseperez/espurna/dashboard)
 [![donate](https://img.shields.io/badge/donate-PayPal-blue.svg)](https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=xose%2eperez%40gmail%2ecom&lc=US&no_note=0&currency_code=EUR&bn=PP%2dDonationsBF%3abtn_donate_LG%2egif%3aNonHostedGuest)
 [![twitter](https://img.shields.io/twitter/follow/xoseperez.svg?style=social)](https://twitter.com/intent/follow?screen_name=xoseperez)
 
 ---
 
+> **2018-05-09**: Default branch in GitHub is now the development branch "dev". The stable branch (the one used to create the binaries) is "[master](https://github.com/xoseperez/espurna/tree/master)".
+
+---
+
 ## Features
 
 * *KRACK* vulnerability free (when built against Arduino Core 2.4.0)