feat(context): add binding.apply(templateFn)

[raymondfeng]

It allows a binding to be configured using a template function that can consistently set up bindings for certain scope/tags.

For example,

const serverTemplate = (binding: Binding) =>
  binding.inScope(BindingScope.SINGLETON).tag('server');
const serverBinding = new Binding<RestServer>('servers.RestServer1');
serverBinding.apply(serverTemplate);

Checklist

• npm test passes on your machine
• New tests added or existing tests modified to cover all changes
• Code conforms with the style guide
• API Documentation in code was updated
• Documentation in /docs/site was updated
• Affected artifact templates in packages/cli were updated
• Affected example projects in examples/* were updated

[bajtos]

The implementation LGTM, I have few minor comments for your consideration.

No further review is needed as far as I am concerned.

[bajtos]

This is an awesome addition to our docs! ❤️