Update include/faunus/physconst.h
Update include/faunus/physconst.h

unit converters can be used as factors
bjornstenqvist/faunus,bjornstenqvist/faunus,gitesei/faunus,mlund/faunus,gitesei/faunus,mlund/faunus,bjornstenqvist/faunus,mlund/faunus,gitesei/faunus