issue #74 - added comment to explain implementation

Author: RobTillaart

README.md

@@ -39,6 +39,7 @@ Miles Burton <miles@mnetcs.com> originally developed this library.
 Tim Newsome <nuisance@casualhacker.net> added support for multiple sensors on
 the same bus.
 Guil Barros [gfbarros@bappos.com] added getTempByAddress (v3.5)
+   Note: these are implemented as getTempC(address) and getTempF(address)
 Rob Tillaart [rob.tillaart@gmail.com] added async modus (v3.7.0)