Report invalid $Action value properly as bug

src/libexec/dottum-install

@@ -25,7 +25,7 @@ dottum__route() {
     case $Action in
         init)       dottum__make_links  ;;
         explore)    dottum__explore     ;;
-        *)          usage       ;;
+        *)          saturnin__bug "bad Action: $Action" ;;
     esac
 }
 export LC_ALL=C