Better error message. (#768)
Better error message. (#768)

* Fix PrivateKeyBytes to error out and fail tests on error.

* Better error message.

pedronasser/caddy,captncraig/caddy,pedronasser/caddy,elcore/caddy,joshix/caddy,dusty/caddy,elcore/caddy,tw4452852/caddy,joshix/caddy,captncraig/caddy,pyed/caddy,dusty/caddy,ollie314/caddy,evermax/caddy,DenBeke/caddy,pyed/caddy,cez81/caddy,cez81/caddy,tobya/caddy,dusty/caddy,evermax/caddy,dusty/caddy,pedronasser/caddy,tobya/caddy,evermax/caddy,yukimochi/caddy,DenBeke/caddy,ollie314/caddy,pyed/caddy,yukimochi/caddy,cez81/caddy,ollie314/caddy,pedronasser/caddy,evermax/caddy,DenBeke/caddy,tw4452852/caddy,joshix/caddy,tw4452852/caddy,devangels/caddy,captncraig/caddy,tobya/caddy,devangels/caddy,elcore/caddy,tobya/caddy,tw4452852/caddy,yukimochi/caddy,pyed/caddy,ollie314/caddy,DenBeke/caddy,devangels/caddy