Add Visualisation for Output Patches

Visual verification/debugging: output patches from Dbihar filter can be shown in one scene with the centreline.
Adjust Derivatives Angles on Bifurcation Patches

Calculate the derivatives at bifurcation points as interpolation of
the adjacent edges. Rotate the rest derivatives to lean towards the
bifurcation point derivatives. This code is work in progress. It is
possible there is some inaccuracy along one of the edges of a patch.