Change to columbia URL for test bathy
Implement new storm surge test using synthetic bathymetry

Also includes new additions to the tests and util modules to support the
fetching of the storm data as well from the NOAA best-track database rather
than relying on somewhere to download it from.
Merge pull request #113 from mandli/fix-bathy-URL

Convert storm-surge test to using synthetic bathymetry
remove calls to axes.set_xticklabels -- not robust.
axis labels come out wrong if zooming or adding additional plots
rotate ticklabels in dtopotools
fix test problem so works if run manually
improved rotation in dtopotools.py
improved rotation in topotools.py
remove un-needed plt.sca
Merge pull request #114 from rjleveque/dtopotools2

remove calls to axes.set_xticklabels -- not robust.
missing import in geoplot.discrete_cmap2
Handle case of single dtopo time for instantaneous uplift
Remove duplicate definition of RefinementData
fgmax_tools: fix fname to input_file_name
dtopotools.convert_to_standard_units should loop over input_units keys
change number of fgmax grids allowed from 2 to 5 by default
Merge pull request #118 from mandli/remove-duplicate-RefinmentData

Remove duplicate definition of RefinementData
Merge pull request #116 from rjleveque/fix_single_dtopo_time

Handle case of single dtopo time for instantaneous uplift
Merge pull request #121 from rjleveque/fix_5.2.1

Fix 5.2.1
fixed a number of bugs in fgmax_tools.py for point_styles other than 2, which had not been exercised