Adds default storage classes for Azure, AWS and vSphere

[mcowger]

What this PR does / why we need it:

This PR adds a default storage class for each of the currently supported IaaS types. Today, only a GCE storageclass is created, leaving AWS, Azure and vSphere users to figure it out on their own. This PR delivers a better out-of-the-box experience

How can this PR be verified?

Deploy to the relevant IaaS, and confirm the storage class exists with: kubectl get sc

Is there any change in kubo-deployment?

No

Is there any change in kubo-ci?

No

Does this affect upgrade, or is there any migration required?

No

Which issue(s) this PR fixes:

#286

Release note:

Adds additional default storageclasses for all supported IaaS.

[cfdreddbot]

:white_check_mark: Hey mcowger! The commit authors and yourself have already signed the CLA.

[cf-gitbot]

We have created an issue in Pivotal Tracker to manage this:

https://www.pivotaltracker.com/story/show/162817550

The labels on this github issue will be updated when the story is started.