Map :) to :simple_smile:

In #1027 (closed) :) was remapped from 😄 (:smile:) to 😀 (:grinning:).

This issue is to propose mapping it to * (:simple_smile:) or 🙂 (:slightly_smiling_face:) instead, for the reasons described in the previous discussion.

* :simple_smile: isn't supported by GitHub, so an image was used to show it here.