Add minimum IAM policy permissions example
Add minimum IAM policy permissions example

For a more restrictive policy where you may have multiple terragrunt
repos storing their state files in a single bucket and using a single
table for state locking, you still want to limit what parts of the
bucket can be modified.

Signed-off-by: Stephen Hoekstra <3b1e522f7a88a63248795498e58fb49766f16364@gmail.com>

tamsky/terragrunt,gruntwork-io/terragrunt,tamsky/terragrunt,gruntwork-io/terragrunt