Provide a name for additional downloads

lib/SlackBuilder/Package.hs

@@ -17,11 +17,12 @@ import qualified Text.URI as URI
 import Crypto.Hash (Digest, MD5)
 import SlackBuilder.Trans
 import Control.Monad.Catch (MonadThrow)
+import Data.Map (Map)
 
 -- | Contains information how a package can be updated.
 data Package = Package
     { latest :: Updater
-    , downloaders :: [Updater]
+    , downloaders :: Map Text Updater
     , category :: Text
     , name :: Text
     }
@@ -79,5 +80,5 @@ renderDownloadWithVersion (DownloadTemplate components) version =
 -- | Function used to get the latest version of a source.
 data Updater = Updater
     { detectLatest :: SlackBuilderT (Maybe Text)
-    , getVersion :: Text -> Text -> SlackBuilderT (URI, Digest MD5)
+    , getVersion :: Text -> Text -> SlackBuilderT Download
     }