Added functions to link to the News API servers.

[phillytan]

The library offers three main functions to get the data. These are getSources, getTopHeadlines, and getEverything. Users may either use method chaining or placing an array into the respective functions in order to send data to the requests.

Example:

These two examples return the same data. They're just different available methods in placing the data.

<?php
include 'vendor/autoload.php';
$newsapi = new NewsAPI\NewsAPI('your_api_key_here');
$request = $newsapi->category('technology')->language('en')->getTopHeadlines();
var_dump($request);

<?php
include 'vendor/autoload.php';
$newsapi = new NewsAPI\NewsAPI('your_api_key_here');
$request = $newsapi->getTopHeadlines([
'category' => 'technology',
'language' => 'en'
]);
var_dump($request);