added unit test for xy (not spherical coords) case which works
readgrid does not include a basemap object if not using spherical coordinates now
working to eliminate instances where it is assumed user wants spherical coordinates
added another case for changing from grid indices to projected space instead of spherical
changed scripts so that usespherical is read in from grid file instead of input
tweak to spherical reading in
changed assumption that tracks are saved in tracks directory
some shape changes so that readfields data can be stored properly
using argmax() as replacement for find()
Merge branch 'do3d' of https://github.com/dcherian/tracpy into do3d