Add a `kreate link` command

Purpose : Develop a new CLI command able to add the @Link ap4k` annotation containing "Link info" to the target endpoint of the microservices to be consumed and where such info is defined as EnvVar for the Deployment(Config). This command is comparable to what `odo link` is doing.
If the info has been added by the user using the @Link ap4k annotation, then the command `kreate link` is irrelevant.

What I'm thinking with the CLI tool is to display the list of the services = endpoints available within the namespace, let the user to select it like also maybe the way to inject the parameters : secret, envar, ... and then enhance the ComponentSpec of the yaml/json file generated OR to append the annotation within the JavaClass with the attributes