Pass document and database to encodeAttribute to mirror decodeAttribute

[kodumbeats]

In #64, we added the ability to pass the document when encoding an attribute:

database/src/Database/Database.php

Lines 1093 to 1105 in 7c26cb3

	/**
	* Decode Attribute
	*
	* Passes the attribute $value, and $document context to a predefined filter
	* that allow you to manipulate the output format of the given attribute.
	*
	* @param string $name
	* @param mixed $value
	* @param Document $document
	*
	* @return mixed
	*/
	protected function decodeAttribute(string $name, $value, Document $document)

This PR extends that functionality to encodeAttribute so we can manipulate the document when trying to encode into a database format.