Add ESP8266 settings to PIO and add default Arduino main

platformio.ini

@@ -7,3 +7,11 @@
 ;
 ; Please visit documentation for the other options and examples
 ; https://docs.platformio.org/page/projectconf.html
+
+[env]
+platform = espressif8266
+board = esp8285
+framework = arduino
+
+[env:release]
+build_flags = -D RELEASE

src/main.c

@@ -0,0 +1,3 @@
+void setup() {}
+
+void loop() {}