Updated README.rst

Author: Gadgetoid

library/README.rst

@@ -10,6 +10,10 @@ Stable library from PyPi:
 
 -  Just run ``sudo pip install enviroplus``
 
+(**Note** that you're best using the git clone / install.sh method below
+if you want all of the UART serial configuration for the PMS5003
+particulate matter sensor to run automatically)
+
 Latest/development library from GitHub:
 
 -  ``git clone https://github.com/pimoroni/enviroplus-python``