Add @composer wrapper for Vimeo PHP library.

This will allow developers to stop copy/paste the class and just add it as a dependency to their development environment via composer.

Simply adding the package to a composer.json file in the root of the developing environment and run ```composer install``` in the prompt.

```json
{
    "require": {
        "vimeo/vimeo-api": "~1.0"
    }
}
```

The package will now be added into a vendor directory in the root of your project. Then add the following to your index.php;

```php
require(__DIR__.'/vendor/autoload.php');
```
Developers will now be able to take full advantage of the Vimeo API class without copy-pasting any files or code.

To add this package to the Packagist Composer repository you'll have to submit it here: https://packagist.org/packages/submit