- Created the CellInfo class and CellTypes Enum.
- CellInfo is used by passing the cell from an ncube to it's constructor.  After that, it will be broken into it's consistent, constituent parts.  This uniformizes the cells, especially valuable for UI editing of cells.
- CellTypes is an enumeration of all supported n-cube cell types.  Use "exp" as the open-ended cell type to create anything additional.  For example, to have a cell be a Map, use a GroovyExpression that returns a map.