_build_index, _pos, _loc, and _delete changes for dense tree-based index
Fixes for _build_index on small len(_lists)
Get delitem working with dense_tree_index
Get tests with full coverage working
Make _build_index faster using list(starmap(add, zip(head, tail)))
Add comments for new index scheme
Add mixed-mode benchmarks for sortedlist: PriorityQueue, Multiset, Ranking, Neighbor, Intervals
Make count faster by inlining and refactoring calls to bisect_left and bisect_right
Make index faster by inlining and refactoring call to bisect_left
Couple more small speed improvement changes to SortedList.index
Add coverage for build_index case when length is one
Change stress to Bash script.
Update implementation docs to reflect new tree-based index
Merge branch 'master' of github.com:grantjenks/sorted_containers