Add support for the a1 and c5n instance families

[mogren]

Cherry pick adding the new instance types to the release-1.3 branch.

The missing instance types are mentioned in #59 and other issues.

Description of changes:
Two new instance types added to vpc_ip_resource_limit.go

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[micahhausler]

LGTM

[benishak]

is this a fix for all instance types of the c5n family?
I had this issue today when I tried to use c5n.9xlarge, I thought it is because it is 9xlarge and it created 8 ENI and added no secondary IPs but 8 Primary IPs. I set max IP for warm up to be 4 and default ENI count to 1. Is it my setting or it is a bug and this PR will fix it? @morgen

[benishak]

I will test tmw with c5.9xlarge

[mogren]

@benishak Yes, the change adds values for c5n.large, c5n.xlarge, c5n.2xlarge, c5n.4xlarge, c5n.9xlarge and c5n.18xlarge.

[mogren]

The 1.3.3 release includes these changes.

To check what you are running currently:

kubectl describe daemonset aws-node --namespace kube-system | grep Image | cut -d "/" -f 2

To get the latest:

kubectl apply -f https://raw.githubusercontent.com/aws/amazon-vpc-cni-k8s/release-1.3/config/v1.3/aws-k8s-cni.yaml

[duraiz]

@mogren We had an issue running "kubectl apply -f https://raw.githubusercontent.com/aws/amazon-vpc-cni-k8s/release-1.3/config/v1.3/aws-k8s-cni.yaml"

It's giving this error

"error: error validating "https://raw.githubusercontent.com/aws/amazon-vpc-cni-k8s/release-1.3/config/v1.3/aws-k8s-cni.yaml": error validating data: ValidationError(CustomResourceDefinition.spec.names): unknown field "scope" in io.k8s.apiextensions-apiserver.pkg.apis.apiextensions.v1beta1.CustomResourceDefinitionNames; if you choose to ignore these errors, turn validation off with --validate=false"

Is it safe to run with this flag "--validate=false" ?

[mogren]

@duraiz Yes, it's safe. The reason for the warning is that we have a "scope" field where it shouldn't be in the release-1.3 branch, but it has been fixed in the master branch. I wanted to keep the changes between 1.3.2 and 1.3.3 minimal to get it out fast, that's why I didn't remove it.