Document new and deprecated MongoBinData subtype constants

Remove discussion about using non-standard types and cross-reference deprecated types with the respective encouraged type.

https://jira.mongodb.org/browse/PHP-962


git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@332748 c90b9560-bf6c-de11-be94-00142212c4b1