Removed threads in truck program, cleaned any errors caused by pika thre...

...ad in iDumpster_central, added DumpsterState enum

@bballtwenty8 

I have made some changes in the iDumpster_central.py as I was facing some poll error. Removed threads in truck program, added DumpsterState so that I don't go behind the same dumpster.

Let me know if my changes aren't being a hindrance to the web_server app. Also for some weird reason, logging/print statements are executed twice. Need to look at this one.