Unittest+BUG: UnitTest for cluster_list and tools and fix the bug
I remove the previous unitest branch and MR because that branch has so complicated history.
I added the cluster_list (get_occurence_counts) and tools (equivalent_deco). equivalent_deco test can be applied to cluster_list class unit test. and fix the mistyping in cluster_list.
Edited by Joonyeob Jeon