code: public byte[] generateImageForMonomer(Monomer monomer, boolean showRgroups)
  			throws BuilderMoleculeException, CTKException, ChemistryException {
  		return Images.generateImageofMonomer(monomer, showRgroups);
  	}
docs: method to generate an image for a monomer
  
  @param monomer
  Monomer Input
  @param showRgroups
  wheter to show the r groups in the image
  @return generated molecule image in byte[]
  @throws BuilderMoleculeException
  if the molecule can not be built
  @throws CTKException
  general ChemToolKit exception passed to HELMToolKit
  @throws ChemistryException
  if the Chemistry Engine can not be initialized