examples: Updated README.txt to reflect changes to platforms/Hakefile
examples: Updated README.txt to reflect changes to platforms/Hakefile

Signed-off-by: Simon Gerber <13ba2e9de9ead0ea0b5f47504fb3a80bb9b1ee3b@inf.ethz.ch>

BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,kishoredbn/barrelfish,BarrelfishOS/barrelfish,kishoredbn/barrelfish,BarrelfishOS/barrelfish,kishoredbn/barrelfish,kishoredbn/barrelfish,kishoredbn/barrelfish,kishoredbn/barrelfish