More unit testing of FieldLattice.set method.
More unit testing of FieldLattice.set method.

fangohr/oommf-python,ryanpepper/oommf-python,ryanpepper/oommf-python,ryanpepper/oommf-python,ryanpepper/oommf-python,fangohr/oommf-python,fangohr/oommf-python