Update readme

README.md

@@ -5,7 +5,7 @@ Power meter monitoring directly on the Pi using Open Energy Monitor and an LDR
 
 I've forked this from yfory's power meter: https://github.com/yfory/power
 
-His uses a capacitor/resistor for the LDR, I use a transistor based circuit instead to provide a digital on/off signal
+His uses a capacitor/resistor for the LDR, I use a transistor based circuit instead to provide a digital on/off signal.
 His version also writes values to an SQLite database and graphs them itself, this does not.
 
 If these features are useful to you, I suggest you check his code.