exit with error message if curl has problems connecting (fixes #133)
exit with error message if curl has problems connecting (fixes #133)

lukas2511/letsencrypt.sh,erorus/letsencrypt.sh,dennisschuerholz/dehydrated,Rayne/letsencrypt.sh,Vitexus/dehydrated,lukas2511/dehydrated,ahnooie/dehydrated