Column grid types

Variables
const int	Renga::GridTypes::Column::Undefined = 0
	Undefined.
const int	Renga::GridTypes::Column::Side = 1
	Side faces of a column.
const int	Renga::GridTypes::Column::Bottom = 2
	Bottom face of a column.
const int	Renga::GridTypes::Column::Top = 3
	Top face of a column.
const int	Renga::GridTypes::Column::Cut = 4
	Faces appearing as a result of cutting a column by other objects.

Possible grid types for a Column mesh