Demo scripts support Conjur OSS and annotation-based authn-k8s

Is your feature request related to a problem? Please describe.

The demo scripts cannot be run directly on a Conjur cluster that has been deployed via Conjur OSS Helm chart. For the Conjur OSS Helm deployed scenario, there is some configuration that needs to be done that is normally done by the kubernetes-conjur-deploy scripts... however, we don't want to muck with the kubernetes-conjur-deploy scripts because those are widely used and we don't want to risk breakage. The bits of configuration that need to be added for Conjur OSS:
- Loading of Conjur policies for the demo
- Initialize the Conjur CA cert
- Followers aren't available with Conjur OSS, so things normally done via followers needs to be done via the Conjur master.
The Conjur OSS helm charts don't deploy a Conjur CLI pod, so this needs to be added for Conjur OSS.
The demo scripts don't support the new style of authn-k8s annotation-based identities.

Support for Conjur OSS server that's been deployed via Helm chart
Have scripts look for a Conjur CLI pod, and create one if it doesn't exist.
Selectable configuration for Annotation-based authentication vs. host-ID-based authentication. (Select via boolean env variable.)