Add nbtk-light-switch.c to translatable files list
Add nbtk-light-switch.c to translatable files list

Fixes MB:#4164 & MB:#4168

pwithnall/mx,jonnylamb/mx,clutter-project/mx,clutter-project/mx,pwithnall/mx,jonnylamb/mx,jonnylamb/mx,jonnylamb/mx,clutter-project/mx,pwithnall/mx,pwithnall/mx,clutter-project/mx