CNAME fix and downcase

I found that I needed to apply the cname fix that was merged for Cap2 into the Cap3 version as well.

I also had to remove the downcase from the elb names: they are case sensitive and (as crazy as it sounds) some of our ELB's ended up with Proper casing and the gem would error.

Hope this helps and thanks for this gem, it really streamlined deploying behind an ELB!