Increase http clients' max_clients to 100

[j3k0]

When some HTTP requests take too long, the queue of requests gets filled up and other requests, that shouldn't fail, fail too with timeouts / too long to process errors.

Logs showed errors like this: [simple_httpclient:137:fetch_impl] max_clients limit reached

So it seems I fell into this case: http://stackoverflow.com/questions/33411493/max-clients-limit-reached-request-queued-tornado

This is a simple (naive?) attempt to fix those errors (based on the stackoverflow answer). Increasing the max number of concurrent requests being processed by tornado seems to fix my problems, on my setup.

[garrettheel]

Thanks for contributing, @j3k0! Would you mind making this a configuration option and only explicitly setting the max number of connections if it is set?