Remove logoURI from token lists
The thornode repository defines the base protocol, and as such it is my view that no frontend details should be included in it.
This removes the icon field from the token lists. Different frontends and apps likely have different sizing, format, and CORS requirements, and almost all likely would be restricted by the update cadence of the develop branch in this repository.
Would affect the following open PRs if the commnunity agrees to merge it: