Add support for custom validation and endorsement plugins.

[Nova38]

What would you like to be added?

Places in code where fix is needed:

In the bellow section to support custom validation and endorsement plugins we just need to be able to specify name of the plugins where in the existing code it is just the const string 'vscc' and 'escc'. It would probably be best if the those are the default values.

https://github.com/hyperledger/bevel-operator-fabric/blob/a4028e5d787a1c988d9cfd5075a5fae7498b3a96/kubectl-hlf/cmd/chaincode/checkcommitreadiness.go#L83-L96

https://github.com/hyperledger/bevel-operator-fabric/blob/a4028e5d787a1c988d9cfd5075a5fae7498b3a96/kubectl-hlf/cmd/chaincode/approve.go#L88-L103

https://github.com/hyperledger/bevel-operator-fabric/blob/a4028e5d787a1c988d9cfd5075a5fae7498b3a96/kubectl-hlf/cmd/chaincode/checkcommitreadiness.go#L83C4-L96

Docs

Here is the doc description of this:
https://hyperledger-fabric.readthedocs.io/en/release-2.5/pluggable_endorsement_and_validation.html

Why is this needed?

In order to be able to experiment with the impact of different ways of implementing endorsement.

[adityajoshi12]

@Nova38 this looks interesting, since you have identified the changes, would be great if you can raise a PR against it.