Format for sending data

[mattinger]

It would be helpful if one could override the data format that is sent. Currently, it appears that it just joins log records with a line separator. However, if one's logging server accepts json data, that won't necessary work:

[ { ... }, { ... } ]

One could achieve the inner json formatting pretty easily with a custom log formatter, and just pushing a json string, and supplying a formatter which printed the log message only.

It would be helpful to overload the push method to accept some form of joiner, so one could potentially wrap those messages inside of a json array element.