Added clone command to README.md

Author: osaether

README.md

@@ -12,6 +12,8 @@ https://www.victronenergy.com/live/open_source:ccgx:setup_development_environmen
 
 You will also need libmodbus v3.1.2 or higher (http://libmodbus.org/).
 
+Clone repo with 'git clone --recursive https://github.com/osaether/dbus-tsmppt.git'
+
 Edit the path to libmodbus in software/dbus-tsmppt.pro, then
 
     cd software