Force cleanup before destroying socket

[fourk]

I noticed that we were occasionally not seeing callbacks fire for reads. I then found that there was a 1:1 correlation between occasions where disconnect executed and this.task was non-null and occasions where we saw no callback for a read.

This patch seems to have fixed it for us.

Thanks for the library!

[fourk]

One thing that was unclear was whether this bug also affects streams. If so, the patch would potentially need to have && this.task.callback removed. We don't use streaming so it's unclear whether or not that behavior is bugged in the same way.

[nlf]

I'm guessing you're probably right and this will have to handle streams too. I'm likely also going to have to make some pooling changes to make this as reliable as possible. Thanks for the patch though, this is a great step in the right direction.