TODO

Data Structures to Add
    * Union-find
    * Fibonacci heap
    * Hash table
    * Bloom filter
    * Skip list

DArray
    * darray_prepend: reserve extra capacity at the front of
      the internal array to amortize the cost of prepending
      elements.
    * darray_slice: figure out the semantics of slices, and
      then add this functionality back.
    * Add iterators
    * Add other functional programming-like operations (map, reduce, etc.)

SList
    * Add sort
    * Add merge
    * Add concat
    * Add iterators
    * Add other functional programming-like operations (map, reduce, etc.)

DList
    * Add merge
    * Add concat
    * Add other functional programming-like operations (map, reduce, etc.)

Binary Heap
    * Add decrease/increase key

Priority Queue
    * Add decrease/increase key

RBTree
    * Maintain pointers to min and max nodes to make iterator begin and end
      operations O(1)

String
    * Add regular expressions
    * Make API less clunky
    * Add unit tests

Graph
    * Keep a separate in-edge list for each node?
    * Write unit tests
    * Make GraphSearchCtx opaque?
    * Maybe separate directed and undirected graphs into different types?
    * Add algorithm for strongly connected components
    * Change Prim and Dijkstra to use Fibonacci heaps
    * Add Kruskal's and Boruvka's MST algorithms when union-find is done
    * Investigate and add network flow algorithms (e.g., Ford-Fulkerson)
    * Add Floyd-Warshall algorithm for all-pairs shortest path
    * Add A* search

Error Handling
    * Asserts: add build-time switch to turn asserts off. This
      would have to then enable alternate logic that would
      gracefully fail instead of blowing up the program.

Memory Management
    * Add a slab allocator to enhance memory performance of
      data structures

Build System
    * Build-time configurations
        - Debug
        - Different backend implementations for
          particular ADTs, e.g., array-based stack
          instead of SList-based.

Documentation
    * Add doxygen-enabled comments to all files
    * Add doxygen step to the build process

Portability
    * Test on 64-bit
    * Test on Linux, OSX