wskdeploy - display the entire deployment plan with detailed API calls

With an interactive mode, `wskdeploy` displays the whole deployment plan and waits for user input to proceed with deployment. Its a very useful feature when users just wants to confirm openwhisk entities being deployed with their manifest and deployment files.

It will be even more useful if we can display API calls along with the deployment plan when `wskdeploy` is invoked in a separate `dry-run` kind of mode.

(Please come with a fancy way of introducing `dry-run` mode)