Make use of Guid for Vertex comparision

[mfe-]

• Define or extend interface of IVertex which makes it possible to use the internal Guid for comparision of vertex1 and vertex2; Possible candidate IComparable<Guid> or IEquatable<IntPtr>
• Adjust algo.

[mfe-]

This issue is also realted to Too many collisions with <250000 edges when comparing with Edge.GetHashCode for transposed #9