too many connections error

[tantalate]

It happens occasionally, here is the reason I found out.
This following URL report 503 with "too many connections" error.
http://127.0.0.1:8991/socket.io/?EIO=3&transport=polling&t=MSvMWqA
Kill and restart the create agent won't solve the problem.

There is a bug with go-engine and solved in recent revision but not within the version used in this project. See this link
Sometimes after killing/restarting the agent, the old Arduino_Create_Bridge process were still running, and still get the old connections counted.

So here we may need to solve the bug that killing/restarting won't terminate the old process, and update the go-engine package to newer version.