;tools: Shake: add "orgfiles" for -VVV, fix their deps

Shake.hs

@@ -745,16 +745,22 @@ main = do
       phony "site" $ do
         need [
            "webmanuals"
-          ,".BACKLOG.md"
-          ,".ROADMAP.md"
+          ,"orgfiles"
           ]
         cmd_ "make -C site build"
 
+      phony "orgfiles" $
+        need [
+           ".BACKLOG.md"
+          ,".ROADMAP.md"
+          ]
+
       -- These org files are converted to markdown for the website.
       [ ".ROADMAP.md"
        ,".BACKLOG.md"
        ] |%> \out -> do
         let src = drop 1 out -<.> "org"
+        need [src]
         liftIO $ writeFile out $ unlines [
            "<!-- " ++ "Generated by \"Shake " ++ out ++ " from " ++ src ++ " -->"
           ,"<div class=\"pagetoc\">"