Add/support a tool for remote debugging.

[rduplain]

Python has many debugging tools. Add or support a tool to attach to and debug a running streamparse component.

[rduplain]

Examples: pyrasite, pdb over socket, celery.contrib.rdb.

[rduplain]

@dan-blanchard says:

It's not well documented, but I actually added remote debugging support using remote_pdb in the last version of streamparse. I needed to debug some stuff, so I threw it in there. You send a SIGUSR1 to the process to get it to drop into the debugger, and then you can just use telnet to connect to it. Right now it only listens on 127.0.0.1 with a random port, so we should probably make those things configurable. https://github.com/Parsely/streamparse/blob/master/streamparse/storm/component.py#L47-L57

[dan-blanchard]

We're using remote_pdb for this now, because it seemed to be the simplest and most up-to-date version of this concept. We just need to better expose this functionality and make it more configurable.