Update install-packages.R
Update install-packages.R

remove devtools based download of portalcasting

weecology/portalPredictions,gmyenni/portalPredictions,sdtaylor/portalPredictions,weecology/portalPredictions,gmyenni/portalPredictions,sdtaylor/portalPredictions,sdtaylor/portalPredictions,weecology/portalPredictions,gmyenni/portalPredictions