Allow for the certificate file to be passed in through the providerArg parameter

[efetoboreakpoguma]

Backgroud

Please see the details about this bug here.

Possible Solution

There are several solutions to this issue but I have opted to go with this one as it involves the smallest possible change.
Currently, the configArg is used to pass in the keyStore value to the JsignJcaProvider. This PR adds the ability to pass in a comma-separated as the configArg where the first element is keyStore and the second element is the configArg.

Also, the configArg can:

• be null.
• contain just the keystore.
• contain both the keystore and certfile.

Testing

See the passed build here.

Summary

As I said above, this is a possible solution. If you decide to go with this approach, we would need to update the docs.