update object model to match implementation from pull #89
update object model to match implementation from pull #89

hsorby/libcellml,nickerso/libcellml,nickerso/libcellml,nickerso/libcellml,nickerso/libcellml,cellml/libcellml,hsorby/libcellml,cellml/libcellml,MichaelClerx/libcellml,MichaelClerx/libcellml,hsorby/libcellml,libcellml/buildbot-testing,MichaelClerx/libcellml,cellml/libcellml,cellml/libcellml,hsorby/libcellml,libcellml/buildbot-testing