refactor class to MetPyMapFeature
refactor class to MetPyMapFeature

ShawnMurd/MetPy,jrleeman/MetPy,ahaberlie/MetPy,ahaberlie/MetPy,jrleeman/MetPy,Unidata/MetPy,Unidata/MetPy,dopplershift/MetPy,dopplershift/MetPy