Added security group tagging
proposal for making orgs a structure with fields instead of just a name field
update error message
Shaving off some unneeded calls, saving CPU cycles

I know it’s very unlikely that a user will notice the difference, but
why range through the list, generate the set and calculate the
hashcode, only to find out that indexMap == nil (e.g. don’t do anything
with the generated hashcode).

As indexMap is only needed when len(parts) > 0, why not only create and
fill it (in one go) when len(parts) > 0?
Update aws-count example with correct github link
terraform: test case for variable count
terraform: validation works with count if default [GH-442]
terraform: set count to 1 while validating [GH-442]
providers/aws: retry deleting security group for some time [GH-436]
helper/resource: RetryError for quitting quickly
providers/aws: only retry dependency violation for security groups
[GH-436]
providers/aws: drain autoscale groups before deleting [GH-435]
providers/aws: if LC not found, delete it [GH-421]
helper/schema: validate Set is a set type [GH-413]
providers/aws: retry destroying internet gateway for some time [GH-447]
Updated changelog for [GH-447]
providers/aws: retry destroying subnet for some time [GH-449]
Updated changelog for [GH-449]
Merge pull request #448 from pmoust/gateway-destroy-retry

providers/aws: retry destroying internet gateway for some time [GH-447]
Merge pull request #449 from pmoust/subnet-destroy-retry

providers/aws: retry destroying subnet for some time [GH-449]