remove 3 build flags

* Removed the webapp-secure build flag, rolling it into the webapp build
  flag.
* Removed the quvi and tahoe build flags, which only adds aeson to
  the core dependencies.
* Removed the feed build flag, which only adds feed to the core
  dependencies.

Build flags have cost in both code complexity and also make Setup configure
have to work harder to find a usable set of build flags when some
dependencies are missing.

Command/ImportFeed.hs

@@ -33,11 +33,9 @@ import Command.AddUrl (addUrlFile, downloadRemoteFile, parseRelaxedOption, parse
 import Annex.Perms
 import Annex.UUID
 import Backend.URL (fromUrl)
-#ifdef WITH_QUVI
 import Annex.Quvi
 import qualified Utility.Quvi as Quvi
 import Command.AddUrl (addUrlFileQuvi)
-#endif
 import Types.MetaData
 import Logs.MetaData
 import Annex.MetaData
@@ -139,16 +137,12 @@ findDownloads u = go =<< downloadFeed u
 		Just (enclosureurl, _, _) -> return $ 
 			Just $ ToDownload f u i $ Enclosure enclosureurl
 		Nothing -> mkquvi f i
-#ifdef WITH_QUVI
 	mkquvi f i = case getItemLink i of
 		Just link -> ifM (quviSupported link)
 			( return $ Just $ ToDownload f u i $ QuviLink link
 			, return Nothing
 			)
 		Nothing -> return Nothing
-#else
-	mkquvi _ _ = return Nothing
-#endif
 
 {- Feeds change, so a feed download cannot be resumed. -}
 downloadFeed :: URLString -> Annex (Maybe Feed)
@@ -193,7 +187,6 @@ performDownload opts cache todownload = case location todownload of
 								else []
 							
 	QuviLink pageurl -> do
-#ifdef WITH_QUVI
 		let quviurl = setDownloader pageurl QuviDownloader
 		checkknown quviurl $ do
 			mp <- withQuviOptions Quvi.query [Quvi.quiet, Quvi.httponly] pageurl
@@ -206,9 +199,6 @@ performDownload opts cache todownload = case location todownload of
 						checkknown videourl $
 							rundownload videourl ("." ++ fromMaybe "m" (Quvi.linkSuffix link)) $ \f ->
 								maybeToList <$> addUrlFileQuvi (relaxedOption opts) quviurl videourl f
-#else
-		return False
-#endif
   where
 	forced = Annex.getState Annex.force