Get load.py working again (perhaps there was a change in netCDF4?)
Add a new c extrema finder, although it's not much faster than current one.

Some testing done and it gives a speedup of ~2, so it could be useful.
Merge any vortmaxes that are too close to eachother.

Whichever has the largest vorticity is assumed to be the primary one.
Enhance plotting, in particular add a plot_match(...) function.

plot_match(...) plots the matching points between a calc'd track and an
ibtracs track, will be very useful!