Umbrella (Tip) descriptor for coloured surfaces

[aniemeyer]

Umbrella descriptor for coloured surfaces can be modified:
Isosceles coloured: Inside the dyclet, colour the face in red, if the opposite edge of the vertex is a base edge.
Wild coloured: Inside the dyclet, colour the face in the colour of the opposite edge.

Umbrella Tip descriptor:
Isosceles coloured: Inside the dyclet, colour the vertex in red, if the edge leading to the vertex is a base edge.
Wild coloured: Inside the dyclet, colour the vertex in colour a, if the colour of the edge leading to the vertex is a