Coordinate systems as individuals

This is a proposal to consider the following coordinate systems as "individuals" instead of "classes" in `nidm-results.owl`: 
- `nidm:Colin27CoordinateSystem`, 
- `nidm:Icbm452AirCoordinateSystem`, 
- `nidm:Icbm452Warp5CoordinateSystem`, 
- `nidm:IcbmMni152LinearCoordinateSystem`, 
- `nidm:IcbmMni152NonLinear2009aAsymmetricCoordinateSystem`, 
- `nidm:IcbmMni152NonLinear2009aSymmetricCoordinateSystem`, 
- `nidm:IcbmMni152NonLinear2009bAsymmetricCoordinateSystem`, 
- `nidm:IcbmMni152NonLinear2009bSymmetricCoordinateSystem`, 
- `nidm:IcbmMni152NonLinear2009cAsymmetricCoordinateSystem`, 
- `nidm:IcbmMni152NonLinear2009cSymmetricCoordinateSystem`, 
- `nidm:IcbmMni152NonLinear6thGenerationCoordinateSystem`, `nidm:Ixi549Space`, 
- `nidm:Mni305CoordinateSystem`

This will support the fact that these terms represent unique well-defined coordinate systems and not classes (potentially corresponding to several coordinate systems).