Update README in regard to ts-interface-builder/macro

[zenflow]

/cc @dsagal

[dsagal]

I saw your other message explaining this change.

I'd like to keep the example here. You are right that it's redundant along with ts-interface-builder's documentation, but the version here is sufficient for a good number of readers, who don't have to get into further details.

How about after this paragraph, adding ### Option 1: Using the CLI with the body as before (including the command line, the example of a generated file, and how to import it), and then ### Option 2: Using the Babel macro with the body containing a link to the details, as well as a snippet of code like

import { getCheckers } from "ts-interface-builder/macro";
const {Square} = createCheckers('./foo.ts');
Square.check({size: 1}); 

ts-interface-checker is the more popular repo, so I think it's good if its README is sufficient to get people to something working.