Add Advanced Custom Fields Fields to the WP REST API - Awesome!

functions.php

function wp_api_encode_acf($data,$post,$context){
	$data['meta'] = array_merge($data['meta'],get_fields($post['ID']));
	return $data;
}

if( function_exists('get_fields') ){
	add_filter('json_prepare_post', 'wp_api_encode_acf', 10, 3);
}