Support sending data over HTTP(s)

It would be nice to add the option to log data to `in_http`.

A common use case is for people who run Fluentd on Heroku (ex: [see this repo](https://github.com/treasure-data/heroku-td-agent).)

NOTE to the maintianers/contributors: this is meant to be one of the projects for Facebook Open Academy =)

Start by tracing how fluent-logger-python currently sends log data and where output destinations are configured. Compare the required HTTP(s) behavior with the in_http use case described in the issue, then identify the project’s existing test entry points and define done as successfully sending logged data over HTTP(s) without breaking current destinations.

Scritto dal modello di indicizzazione a partire dal testo della issue.