Automatically create a dynamically provisioning StorageClass

[patrickmslatteryvt]

Add option to automatically create a dynamically provisioning StorageClass after the GlusterFS daemon-set deployment has completed.

To automatically create a StorageClass named: glusterfs-storage

./gk-deploy --yes --deploy-gluster --namespace glusterfs --create-dynamic-sc

To automatically create a StorageClass named: glusterfs-ssd-storage

./gk-deploy --yes --deploy-gluster --namespace glusterfs --create-dynamic-sc --dynamic-sc "glusterfs-ssd-storage"

I don't have access to an OpenShift cluster to test this against so I didn't include the template for OpenShift.

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This change is 

[centos-ci]

Can one of the admins verify this patch?

[jarrpa]

Thanks for the PR! I don't think we need to bother having two flags. Just use one --storage-class flag, where it can be in one of three states:

• Default value of "", no SC
• If flag is specified but with no value, default value of glusterfs
• If flag is specified with a value, use that as the SC name.

[patrickmslatteryvt]

OK, sure. I can make those changes.

[jarrpa]

Close, but not quite. I want the default value at the top of the file to be "". If the option is specified, that value changes to "glusterfs", and if the option is specifies a value then that value is used as the StorageClass name.

[patrickmslatteryvt]

OK, I messed up on the last one, I get what you mean now. I'll fix it in a day or two, I need to make another test cluster to validate it on first...

Also I was thinking I could add an option to set the StorageClass as default, your thoughts?

[jarrpa]

Couldn't hurt to add it. --storage-class-default or something like that.

[ansiwen]

How about a --storage-class-volumetype option as well? For minikube I would need volumetype: "none", and it would be nice to use this new feature.