Let's start using the discussion panel!

[wkentaro]

Hi, all!

I decided to start using the discussion panel GitHub recently introduced.
As it is designed to be more community involved, I think it makes sense to move the following categories from the issues panel to the discussions panel.

• feature requests
• questions

Let's keep bugs as it is and reported them in the issues panel.
I'll slowly sort the issues out by migrating them to the discussions panel if necessary.