Document Updated for filter method

[devbysn]

documentation for filter method updated.

[jsumners]

Thank you for taking this on, @devbysn. When I opened the "good first issue" I expected that the true fix would be a while coming (as in, I didn't plan to deprecate the subX properties any time soon). But the work has been started by a community member in ldapjs/filter#5 to do just that. Given that PR is progressing, I think that changing this documentation would be unnecessary. What do you think?

[devbysn]

Sure, @jsumners .
i will check other issues, will check if i can help in any.

[jsumners]

Thanks. I'm going to go ahead and close this, and the issue, as being solved in a different manner.