Provide way to set custom query parser
The recommended way with koa-qs module is not acceptable for me in few reasons:
1) I want to customize the default qs behavior, but this module doesn't provide this possibility.
2) The module is not updated for a long time.
3) It is just looks as awful side effect kode.

I'm asking you to provide some simple syntax to set custom query parser. Maybe with a constructor of koa instance or something like that.