v1.3.3

1. Fix bugs in RasterizeGraph edge coloring
2. Resample Node no longer results in volume shrinkage by 1 pixel
3. SpecifiedLocation won't get stuck in an infinite loop if None of the points to choose from are valid, instead throws an error.
4. removed references to np.float128 which may not be available on all platforms (mac). Tests now pass on mac.
5. Removed code for python 2 compatibility
6. padding falls back on 'constant' if mode provided is not supported