Fix for #664, crashed due to ig.Attachements being 0
Usage info for graph command was actually that of output
provider/aws: fixing the aws_internet_gateway resource

The resource is build so it can attach and detach the Internet Gateway
from a VPC, but as the schema has `Required` and `ForceNew` both set
to `true` for the vpc_id field it will never use these capabilities.
Small gofmt update...
Merge pull request #667 from svanharmelen/f-fix-schema-aws-internet-gateway

provider/aws: fixing the aws_internet_gateway resource
Setting the VPC id to blank for unattached igws
Merge pull request #666 from donjohnson/patch-1

Usage info for graph command was actually that of output
Merge pull request #665 from gosuri/master

Fix for #664, crashed due to ig.Attachements being 0
Making all function names consistent

Before all providers were using the helper.Schema approach the helper
function had these names. Now they all use names consistent with the Go
naming conventions except for these last few…
Merge pull request #674 from svanharmelen/f-make-func-names-consistent

Making all function names consistent