Fixed broken well class. Added functionality to add phiramp if mfnwt model defined.
Fixed broken well class. Added functionality to add phiramp if mfnwt model defined.

brclark-usgs/flopy,brclark-usgs/flopy,jentjr/flopy,aleaf/flopy,bdestombe/flopy-1,jentjr/flopy,aleaf/flopy,mrustl/flopy