1.0.3
 * Massive speed increase in the loop which calculates dipole fields (~50-100x) thanks to executing the loop entirely in NumPy rather than as a Python for loop.
 ** See http://stackoverflow.com/questions/2586749/what-is-the-most-platform-and-python-version-independent-way-to-make-a-fast-loop
 * Some minor bugfixes

1.0.1
 * can now draw fields between selected values, so you can draw fields where infinities are present.