All framed vertices now implement VertexFrame and all framed edges implement EdgeFrame.

Irrespective of if the framed interface extends VertexFrame or EdgeFrame the proxy returned will always implement these interfaces.

This is prep work for https://github.com/tinkerpop/frames/pull/11 as annotation handlers no longer need to know about the method of framing (currently java proxy), instead they use VertexFrame or EdgeFrame.