NF: new code to slice 4d or 5d data
NF: start cleanup of redundant code in util
BF: make_cost_thresh_lookup has correct order of costs and associated thresholds
NF: change make_cost_thresh_array to return a record array for added clarity
RF: cost2thresh calls cost2thresh2 to minimize code duplication, added tests
RF: finish cleaning up cost to thresh, caught corner case in slice data
NF: add tests and replace function with duplicate bevaiour with corresponding numpy functions
RF: replace old code that has been included in numpy with corresponding numpy calls
NF: add test_threshold_adjacency_matrix, small cleanup
BF: fix code in format_matrix, update tests
NF: add function to find true cost associated with thresholded array (and tests), doc cleaning
Merge pull request #11 from cindeem/util_edits

Utils updated to generate boolean arrays, code cleanup