Add OpenEBS CNCF as an app

[elyesbenamor]

Expected Behaviour

Add CNCF openEBS as an app
arkade install openebs

Current Behaviour

App not part of arkade list
I have already created local fork/openebs branch in my forked project and tested it.
It only needs approval to create a PR.

Details

Openebs CNCF link: https://www.cncf.io/projects/openebs/
Dynamic PV provisioning and it is very useful for dev or production grade environment.
list of Openebs Use cases : https://openebs.io/docs/introduction/usecases

[elyesbenamor]

@alexellis would be interested to include this as an app?

[elyesbenamor]

@alexellis can we add this app ?