Add Amazon EC2 support

Follow a similar structure as the Rackspace provider.

EC2 required a small change to autoInstaller - it requires apt-get
update to be ran twice. If you read the output from the two times it is
different each time and allows the next install to go through. Without
the second apt-get update the apt-get install will fail.

Provide easy way of setting up required environment variables through
setupEC2.sh.

OSEHRA-Id: http://issues.osehra.org/browse/VAF-156
Change-Id: Ic59b8f727145405d090733d1619c229d149cf182
Merge "Add Amazon EC2 support"