fix(studio-ui-codegen-react): include all imports used in generated components

[dpilch]

Resolved #37

Include all necessary imports in generated React components. Also sort named
imports.

Using this Studio component will produce the following React component.

{
  appId: 'd37nrm8rzt3oek',
  bindingProperties: {},
  componentType: 'Box',
  environmentName: 'staging',
  componentId: 's-s4mU579Ycf6JGHwhqT',
  name: 'aawwdd',
  overrides: {},
  properties: {},
  variants: [],
}

/* eslint-disable */
import React from "react";
import { EscapeHatchProps, View, getOverrideProps } from "@aws-amplify/ui-react";

export type aawwddProps = {} & {
    overrides?: EscapeHatchProps | undefined | null;
};
export default function aawwdd(props: aawwddProps): JSX.Element {
    return (<View {...props} {...getOverrideProps(props.overrides, "View")}></View>);
}

JSX is included in global scope for Typescript.

[frimfram]

LGTM!

[johnpc]

it works!