Issue with documentation.build

Hey given this JS doc

```js
/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
* @providesModule Alert
* @flow
*/
'use strict';

const AlertIOS = require('AlertIOS');
const NativeModules = require('NativeModules');
const Platform = require('Platform');

import type { AlertType, AlertButtonStyle } from 'AlertIOS';

type Buttons = Array<{
text?: string,
onPress?: ?Function,
style?: AlertButtonStyle,
}>;

type Options = {
cancelable?: ?boolean,
onDismiss?: ?Function,
};

/**
* Launches an alert dialog with the specified title and message.
*
* Optionally provide a list of buttons. Tapping any button will fire the
* respective onPress callback and dismiss the alert. By default, the only
* button will be an 'OK' button.
*
* This is an API that works both on iOS and Android and can show static
* alerts. To show an alert that prompts the user to enter some information,
* see `AlertIOS`; entering text in an alert is common on iOS only.
*
* ## iOS
*
* On iOS you can specify any number of buttons. Each button can optionally
* specify a style, which is one of 'default', 'cancel' or 'destructive'.
*
* ## Android
*
* On Android at most three buttons can be specified. Android has a concept
* of a neutral, negative and a positive button:
*
* - If you specify one button, it will be the 'positive' one (such as 'OK')
* - Two buttons mean 'negative', 'positive' (such as 'Cancel', 'OK')
* - Three buttons mean 'neutral', 'negative', 'positive' (such as 'Later', 'Cancel', 'OK')
*
* By default alerts on Android can be dismissed by tapping outside of the alert
* box. This event can be handled by providing an optional `options` parameter,
* with an `onDismiss` callback property `{ onDismiss: () => {} }`.
*
* Alternatively, the dismissing behavior can be disabled altogether by providing
* an optional `options` parameter with the `cancelable` property set to `false`
* i.e. `{ cancelable: false }`
*
* Example usage:
* ```
* // Works on both iOS and Android
* Alert.alert(
* 'Alert Title',
* 'My Alert Msg',
* [
* {text: 'Ask me later', onPress: () => console.log('Ask me later pressed')},
* {text: 'Cancel', onPress: () => console.log('Cancel Pressed'), style: 'cancel'},
* {text: 'OK', onPress: () => console.log('OK Pressed')},
* ],
* { cancelable: false }
* )
* ```
*/
class Alert {

static alert(
title: ?string,
message?: ?string,
buttons?: Buttons,
options?: Options,
type?: AlertType,
): void {
if (Platform.OS === 'ios') {
if (typeof type !== 'undefined') {
console.warn('Alert.alert() with a 5th "type" parameter is deprecated and will be removed. Use AlertIOS.prompt() instead.');
AlertIOS.alert(title, message, buttons, type);
return;
}
AlertIOS.alert(title, message, buttons);
} else if (Platform.OS === 'android') {
AlertAndroid.alert(title, message, buttons, options);
}
}
}

/**
* Wrapper around the Android native module.
*/
class AlertAndroid {

static alert(
title: ?string,
message?: ?string,
buttons?: Buttons,
options?: Options,
): void {
var config = {
title: title || '',
message: message || '',
};

if (options) {
config = {...config, cancelable: options.cancelable};
}
// At most three buttons (neutral, negative, positive). Ignore rest.
// The text 'OK' should be probably localized. iOS Alert does that in native.
var validButtons: Buttons = buttons ? buttons.slice(0, 3) : [{text: 'OK'}];
var buttonPositive = validButtons.pop();
var buttonNegative = validButtons.pop();
var buttonNeutral = validButtons.pop();
if (buttonNeutral) {
config = {...config, buttonNeutral: buttonNeutral.text || '' };
}
if (buttonNegative) {
config = {...config, buttonNegative: buttonNegative.text || '' };
}
if (buttonPositive) {
config = {...config, buttonPositive: buttonPositive.text || '' };
}
NativeModules.DialogManagerAndroid.showAlert(
config,
(errorMessage) => console.warn(errorMessage),
(action, buttonKey) => {
if (action === NativeModules.DialogManagerAndroid.buttonClicked) {
if (buttonKey === NativeModules.DialogManagerAndroid.buttonNeutral) {
buttonNeutral.onPress && buttonNeutral.onPress();
} else if (buttonKey === NativeModules.DialogManagerAndroid.buttonNegative) {
buttonNegative.onPress && buttonNegative.onPress();
} else if (buttonKey === NativeModules.DialogManagerAndroid.buttonPositive) {
buttonPositive.onPress && buttonPositive.onPress();
}
} else if (action === NativeModules.DialogManagerAndroid.dismissed) {
options && options.onDismiss && options.onDismiss();
}
}
);
}
}

module.exports = Alert;
```

When I run it though the `documenation.build() ... documentation.format.md()` I get this markdown

```md

##

Copyright (c) 2015-present, Facebook, Inc.
All rights reserved.

This source code is licensed under the BSD-style license found in the
LICENSE file in the root directory of this source tree. An additional grant
of patent rights can be found in the PATENTS file in the same directory.

## Alert

Launches an alert dialog with the specified title and message.

Optionally provide a list of buttons. Tapping any button will fire the
respective onPress callback and dismiss the alert. By default, the only
button will be an 'OK' button.

This is an API that works both on iOS and Android and can show static
alerts. To show an alert that prompts the user to enter some information,
see `AlertIOS`; entering text in an alert is common on iOS only.

## iOS

On iOS you can specify any number of buttons. Each button can optionally
specify a style, which is one of 'default', 'cancel' or 'destructive'.

## Android

On Android at most three buttons can be specified. Android has a concept
of a neutral, negative and a positive button:

- If you specify one button, it will be the 'positive' one (such as 'OK')
- Two buttons mean 'negative', 'positive' (such as 'Cancel', 'OK')
- Three buttons mean 'neutral', 'negative', 'positive' (such as 'Later', 'Cancel', 'OK')

By default alerts on Android can be dismissed by tapping outside of the alert
box. This event can be handled by providing an optional `options` parameter,
with an `onDismiss` callback property `{ onDismiss: () => {} }`.

Alternatively, the dismissing behavior can be disabled altogether by providing
an optional `options` parameter with the `cancelable` property set to `false`
i.e. `{ cancelable: false }`

Example usage:

// Works on both iOS and Android
Alert.alert(
'Alert Title',
'My Alert Msg',
[
{text: 'Ask me later', onPress: () => console.log('Ask me later pressed')},
{text: 'Cancel', onPress: () => console.log('Cancel Pressed'), style: 'cancel'},
{text: 'OK', onPress: () => console.log('OK Pressed')},
],
{ cancelable: false }
)

## AlertAndroid

Wrapper around the Android native module.
```

Problem is, as you'll notice on line 3, there is an empty `##` which is breaking things in ast. Am I missing something or is this a bug?