remove apfField.h from crvVtk.cc
remove apfField.h from crvVtk.cc

apfField.h is an internal header,
and luckily it wasn't quite needed here

YetAnotherMinion/core,yangf4/core,yangf4/core,YetAnotherMinion/core,yangf4/core,YetAnotherMinion/core,yangf4/core,YetAnotherMinion/core,YetAnotherMinion/core,yangf4/core