More graceful failure during shutdown

[bzier]

Shutting down the HTTP Server sometimes fails with a broken pipe. It seems like this may be because the emulator process has already stopped by the time the server tries sending the response. This situation should be handled more gracefully. Relevant code

[bzier]

This isn't exactly the same error as described above (haven't actually seen that one in a long time). However, another somewhat related issue is that if you close() the environment, and you then attempt to make() a new one in the same python process, make() fails with:

socket.error: [Errno 98] Address already in use

Found a resolution to this by adding the following line to my shutdown() method:

super(ControllerHTTPServer, self).server_close()

Noting this here to come back on another branch later. In the middle of other stuff right now.