InversionPoset[n] returns a Hasse diagram of the partially ordered set on size- permutations in which if can be obtained from by an adjacent transposition that places the larger element before the smaller.
The function takes two options: Type and VertexLabel, with default values Undirected and False, respectively.
When Type is set to Directed, the function produces the underlying directed acyclic graph. When VertexLabel is set to True, labels are produced for the vertices.
