fixes #79; note that hightlightNode sucks
fixes #79; note that hightlightNode sucks

It should be implemented as setting a chosen state, containing id's of
chosen nodes and possibly links as well (although links are defined by
their source and target ids).

Rhizi/rhizi,cben/rhizi,Rhizi/rhizi,shlomif/rhizi,tlevine/rhizi,ozFri/rhizi,shlomif/rhizi,cben/rhizi,tlevine/rhizi,ozFri/rhizi,yuvadm/rhizi,cben/rhizi,ozFri/rhizi,shlomif/rhizi,yuvadm/rhizi,Rhizi/rhizi,ozFri/rhizi,tlevine/rhizi,tlevine/rhizi,Rhizi/rhizi,yuvadm/rhizi,shlomif/rhizi,cben/rhizi,yuvadm/rhizi