Added some sanity checks so that missing 'node' arguments don't kill the whole page!
Added some sanity checks so that missing 'node' arguments don't kill the whole page!

Ensembl/ensembl-webcode,Ensembl/ensembl-webcode,Ensembl/ensembl-webcode,Ensembl/ensembl-webcode,Ensembl/ensembl-webcode