Partial support for variable-sized bins in MantelCorrelogram class.
Merge branch 'master' into mantel_correlogram_bins
Added MantelCorrelogram._find_row_col_indices(), which is necessary for variable-sized bins.
Added variable-size bin support to MantelCorrelogram._find_distance_classes().
Added --variable_size_distance_classes option to compare_distance_matrices.py script.
Fixed a couple of border-case bugs and added tests for them.
Added notes to changelog; reverted a few comments I didn't mean to add.
Merge pull request #627 from jrrideout/mantel_correlogram_bins

Added support for variable-size distance classes in Mantel correlogram.