message: core: expose decorate function
  I know people can call decorators by themselves but with decorate function you can set many of them on an object
diff: -import { Container, interfaces } from 'inversify';
  +import { Container, interfaces, decorate } from 'inversify';
  import { Provider, Type, ValueProvider, ClassProvider } from './types';
  +export { decorate };
  +
  export class Injector extends Container {
  public provide(provider: Provider): void {
  if (Array.isArray(provider)) {
  