Read and write SMILES atom class using the ATOM_ATOM_MAPPING property.

Signed-off-by: Egon Willighagen <egonw@users.sourceforge.net>
Optionally turn off the generation of SMILES with atom class information.

Signed-off-by: Egon Willighagen <egonw@users.sourceforge.net>
Don’t initialise chem object properties on read - note getProperties() still initialises the properties.

Signed-off-by: Egon Willighagen <egonw@users.sourceforge.net>
SmilesGenerator new functionality documentation.

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