allow pairs to be specified on the command-line using ':' as well as ','
allow pairs to be specified on the command-line using ':' as well as ','

percyliang/fig,ppasupat/fig,percyliang/fig,ppasupat/fig,percyliang/fig,percyliang/fig,ppasupat/fig,ppasupat/fig,ppasupat/fig,percyliang/fig,ppasupat/fig,percyliang/fig