Clean-up volume creation.

A few minor comment fixes
Initial version (copied over from MapR-on-GCE repository)
Changed VPC model to use node0 as NAT server for remaining nodes.
Added script to configure NAT services on AWS node.
First version
Minor fix during EPEL installation (forgot to quote ENV var that could
be null)
The security group for MapR clusters should allow
egress for ports 80 and 443 so that http:// access to external
sites is guaranteed to work.
Comment changes
Bug in ami-launch-index meta-data for VPC instnaces ... had to implment
a workaround.
Updates for VPC support
Fix for bug 11649 (ThreadStack too small for CLDB)
Final fixes to make VPC work.

Added logic so error output for ec2 commands goes to local file (so
we can check it after the fact if something goes wrong).
Reworked logic to store ssh keys in cluster for exchange
to "worker" nodes.
One more AMI documented.
Restructued EPEL configuration to support Amazon Linux instance
types (where EPEL is in place but unconfigured).
for dev
zap most cookbooks in favor of berkshelf mgmt
Berksfile management of cookbook dependencies... finally
Save off MapR.disks file to simplify restart
Handle sdparm in a special model, since the Amazon Linux AMI's
don't have that package in any of their default repos.