Partition extended tetrahedral elements

Signed-off-by: Egon Willighagen <egonw@users.sourceforge.net>
In memory identity template library.

Signed-off-by: Egon Willighagen <egonw@users.sourceforge.net>
2D identity templates created from ChEBI 118. Tools are in 'cdk-build-util' but not committed yet (depend on this patch).

Signed-off-by: Egon Willighagen <egonw@users.sourceforge.net>
Utility to create skeleton copies of molecules. These are normalized representations when every except the element type is removed.

Signed-off-by: Egon Willighagen <egonw@users.sourceforge.net>