`_send_to_plotly` now replaces a figure's '\n' with '<br>'.

In response to (5) in https://github.com/plotly/python-api/issues/46
I vote no, cuz I don't think people will actually use it. I would like people to be able to type `tools.` <tab> <tab> or `help(tools)` and get a real good, quick idea of what is available and useful to them