The holos cli does not use an interface to handle different Platform api
versions. This makes it difficult to evolve the API in a backwards
compatible way.
This patch adds a top level switch statement to the `holos render
platform` command. The switch discriminates on the Platform API
version. v1alpha3 and earlier are classified as legacy versions and
will use the existing strict types. v1alpha4 and later versions will
use an interface to render the platform, allowing for multiple types to
implement the platform rendering interface.
Previously the top level logger used a json handler while the rest of
the code used the default console handler. This patch unifies them to
be consistent.
