VertexDict precision fails for high-poly objects

[rystills]

When generating vertices and storing them in a VertexDict, some verts fail to be generated if they are too close together. This is likely an issue with the current precision system used by VertexDict addVert and getVert. This can be verified by making a cylinder from meshShapes with a very large segment count (300+ depending on shape extents). Vertex position precision should be re-evaluated to accommodate models with high densities of vertices, as failing to generate verts can cause other components of the generation system to fail.