Deprecate Zend\Dom\Query in favor of more logical OO approach

Hello everyone,

I am quite a heavy user of DOMDocument XPath queries and I have always been bothered by the Dom implementation in ZF2. The Zend\Dom\Query class seems very illogical as an object and contains quite a lot of inefficiencies and lacks access to the used DOMDocument generated from a string.

I created Zend\Dom\Document which makes more sense, because we are querying this object and not the other way around (creating a Query object that generates a DOMDocument which we then query and that we can't even access).

`Zend\Dom\Query` class:

 ```php
$query = new Query($html);
$query->execute('a'); // Generation of a DOMDocument
$query->execute('span'); // Generation of another DOMDocument from the same input string
$query->getDOMDocument(): // Impossible
```

`Zend\Dom\Document` class:

 ```php
$document = new Document($html);
$document->query('a', Document::QUERY_CSS);
$document->query('//span', Document::QUERY_XPATH);
$dom      = $document->getDomDocument();
$dom->createTextNode('<node></node>');
 ```

Problems solved:
* Addition of a method to get the created DOMDocument instance
* Caching of generated DOMDocument on each query
* More logical object (Document VS Query)
* Only one method to query a document

The methods more or less stay the same, I reused the tests already available for Query and added some for the new behavior. I deprecated Zend\Dom\Query in favor of this new class.

I'm in favor of adding this to a ZF2.* future release because I consider this more like an a new feature (new logic & different object) than a component refactor. ZF3 is very far away and Zend\Dom is currently lacking a proper DOMDocument wrapper.