Extract sandbox and fake into separate modules

I'd like to propose a way how we can make sinon more modular and allow to compose a version that only has the fake API and no spy, stub, mock and ideally also has optional lolex and nise.

Why?

The API surface of Sinon is too large and removing APIs is really difficult and a long process. Therefore, we might just keep it the way it is, have Sinon integrate all the features that we offer, but maybe allow to compose smaller installations as well.

How?

With #2144 I have separated the fake implementation from spy. This makes it possible to

• move the common logic from util into @sinonjs/commons
• extract the proxy.js, call.js, call-util.js, fake-api.js, ... into a separate module. Maybe @sinonjs/proxy?
• extract a minimal, generic sandbox implementation that just offers hooks to install things on it, maybe called @sinonjs/sandbox. This would become the sinon default sandbox instance.
• extract the fake.js implementation into @sinonjs/fake.

There are multiple options how fake, lolex and nise could be registered on the sandbox then.

What do you think?

Start by reviewing the separation described in #2144 and the existing fake, proxy.js, call.js, call-util.js, fake-api.js, util, sandbox, lolex, and nise components. Clarify the desired module boundaries and registration approach before changing code; done would mean a decided, modular extraction plan that supports the proposed smaller installations.