Standalone dash renderer (for custom hooks) - March 1

[valentijnnieman]

This enables the dash-renderer to be called as a standalone class, so that we can pass config objects to it.

Depends on this PR that enables dash-renderer to be a standalone class to be merged (also see this PR for an example of how to use a custom DashRenderer instance).

[chriddyp]

This side of the code is looking good to me! @T4rk1n could you take a look as well?

[T4rk1n]

Looks good, only a couple minor changes.

Also before release, would we need to lock the version of dash-renderer in setup.py since the starting of the renderer has changed and now needs the new Renderer syntax ?

[Akronix]

Hi. Can I ask how is the status of this? Is it in your roadmap or is there any tentative date for its release?

[alexcjohnson]

OK, I think we're home free! Thanks for the changes this morning @valentijnnieman!
💃
The conflicts in requirements can be resolved in favor of the current master:
-e git://github.com/plotly/dash-renderer.git@master#egg=dash_renderer
if the renderer PR is merged first so that's on master.