Improve subcomponent and components with "parts" exports

[cgatian]

Allow components exported as "Parts" to be extracted. In addition it also addresses 2 of the 4 export syntaxes mentioned in #324. I didn't fix all the syntaxes because I didn't want to make too many changes, but certainly can follow-up.

Adds fixes for the following scenarios:

---

import * as React from 'react';

interface LabelProps {
  /** title description */
  title: string;
}

/** SubComponent description */
const SubComponent = (props: LabelProps) => (
  <div>My Property = {props.title}</div>
);

interface StatelessStaticComponentsProps {
  /** myProp description */
  myProp: string;
}

/** StatelessStaticComponents description */
const StatelessStaticComponents = (props: StatelessStaticComponentsProps) => (
  <div>My Property = {props.myProp}</div>
);

export const Record = {
  Comp1: StatelessStaticComponents,
  Comp2: SubComponent
};

---

import * as React from 'react';

interface LabelProps {
  /** title description */
  title: string;
}

/** StatelessStaticComponents.Label description */
const SubComponent = (props: LabelProps) => (
  <div>My Property = {props.title}</div>
);

interface StatelessStaticComponentsProps {
  /** myProp description */
  myProp: string;
}

/** StatelessStaticComponents description */
const StatelessStaticComponents = (props: StatelessStaticComponentsProps) => (
  <div>My Property = {props.myProp}</div>
);

export const Components = {
  StatelessStaticComponents,
  SubComponent
};

---

import * as React from 'react';

interface LabelProps {
  /** title description */
  title: string;
}

/** StatelessStaticComponents.Label description */
const SubComponent = (props: LabelProps) => (
  <div>My Property = {props.title}</div>
);

interface StatelessStaticComponentsProps {
  /** myProp description */
  myProp: string;
}

/** StatelessStaticComponents description */
const StatelessStaticComponents = (props: StatelessStaticComponentsProps) => (
  <div>My Property = {props.myProp}</div>
);

StatelessStaticComponents.Label = SubComponent;

export { StatelessStaticComponents };

---

import * as React from 'react';

interface LabelProps {
  /** title description */
  title: string;
}

/** StatelessStaticComponents.Label description */
const SubComponent = (props: LabelProps) => (
  <div>My Property = {props.title}</div>
);

interface StatelessStaticComponentsProps {
  /** myProp description */
  myProp: string;
}

/** StatelessStaticComponents description */
function StatelessStaticComponents(props: StatelessStaticComponentsProps) {
  return <div>My Property = {props.myProp}</div>;
}

StatelessStaticComponents.Label = SubComponent;

export { StatelessStaticComponents };

Fixes #324