[install-federated] Add option for sequential startup to get better logs

bin/install-federated

@@ -123,7 +123,13 @@ done
 for i in "${EXTRA_APPS[@]}"; do
   . /federated/lib/$i.sh
   config_$i
-  start_$i &
+  if [ "x$PARALLEL_STARTUP" != "xfalse" ]; then
+    start_$i &
+  else
+    # Startup in sequence is slower, but produces much
+    # clearer debug output on an installation failure
+    start_$i
+  fi
 done
 
 wait