Renamed 'using' to 'applying' - clearer than both previous names
Renamed 'using' to 'applying' - clearer than both previous names

The name of this utility should now be settled. In common useage
'applying' and 'using' have similar semantics but 'applying' has the
more correct technical term (see Python's apply built-in).

ioam/lancet,melver/lancet