Implements 'jsnx.generators.classic.grid_2d_graph' (jsnx.grid_2d_graph).
Adds a new Jasmine matcher, toEqualAny.

Some graph operations don't have a unique result. Since the order in
which objects are iterated over is implementation dependent, different
browsers can return different results for the same graph.

This methods accepts a list of values to compare a result against and
passes successfully if the result is equal to at least one of them.
Implements 'algorithms/shortest_paths/unweighted'.

Adds the following methods:

- jsnx.algorithms.shortest_paths.unweighted.single_source_shortest_path_length
  (jsnx.single_source_shortest_path_length)
- jsnx.algorithms.shortest_paths.unweighted.all_pairs_shortest_path_length
  (jsnx.all_pairs_shortest_path_length)
- jsnx.algorithms.shortest_paths.unweighted.bidirectional_shortest_path
  (jsnx.bidirectional_shortest_path)
- jsnx.algorithms.shortest_paths.unweighted.single_source_shortest_path
  (jsnx.single_source_shortest_path)
- jsnx.algorithms.shortest_paths.unweighted.all_pairs_shortest_path
  (jsnx.all_pairs_shortest_path)
- jsnx.algorithms.shortest_paths.unweighted.predecessor
  (jsnx.predecessor)