Couple changes for a Mac

Author: lbussy

platformio.ini

@@ -9,13 +9,13 @@
 ; https://docs.platformio.org/page/projectconf.html
 
 [common_env_data]
-upload_speed = 921600
+upload_speed = 460800 ; 921600
 monitor_speed = 74880
 framework = arduino
 platform = espressif8266
 build_unflags = 
 build_flags =
-    !python tools\git_rev.py
+    !python tools/git_rev.py
     -D PIO_SRC_TAG=2.2.2
     -D BAUD=${common_env_data.monitor_speed}
     -DDEBUG_ESP_PORT=Serial