Added the ability to apply extra volumes and volume mounts to the daemonset

[FutureMatt]

What this PR does / why we need it:
Adds the ability for the end-user to mount extra volumes into the DaemonSet pod. In our instance we want to leverage the CA file configuration option to validate the vCenter instance we are connecting to and this needs to be mounted in the pod.

I also spotted that the affinity parameters were missing from the readme so I added that too.

[k8s-ci-robot]

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This pull-request has been approved by: FutureMatt
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[k8s-ci-robot]

Hi @FutureMatt. Thanks for your PR.

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