use explicit import list from Prelude to avoid name class with `catch` when using old base.
use explicit import list from Prelude to avoid name class with `catch` when using old base.

erantapaa/happstack-server,Happstack/happstack-server,erantapaa/happstack-server,arybczak/happstack-server,Happstack/happstack-server,arybczak/happstack-server