React

- Documentation updates.

- **Possibly breaking change** render_component now accepts a `request_headers` keyword argument.
There are some edge-cases where this may break down-stream code. If you are overriding
part of the render pipeline, you may need to ensure that you are using `**kwargs` to read and/or pass wildcard arguments.
([Ben Ilegbodu](https://github.com/benmvp))
https://github.com/markfinger/python-react/pull/64
- [Documentation] Fix outdated link to server.js
([Jonathan Cox](https://github.com/geezhawk))
https://github.com/markfinger/python-react/pull/60
- [Examples] missing babel-preset-es2015 in package.json in Tornado-example
([付雨帆](https://github.com/letfly))
https://github.com/markfinger/python-react/pull/59
- [Examples] Added missing dependency on babel-preset-es2015
([Rune Juhl Jacobsen](https://github.com/runejuhl))
https://github.com/markfinger/python-react/pull/56
- [Examples] Added es6 compiler plugin to .bablerc in basic_rendering
([Pringels](https://github.com/Pringels))
https://github.com/markfinger/python-react/pull/55

- **Breaking change** The base renderer's __init__ no longer accepts the RENDER_URL setting as an argument.
The url is now resolved during calls, rather than initialisation.
- When used in companion with Django, settings will now be dynamically fetched rather than bound on
initialisation. This enables a codebase to be more easily controlled from a test suite
- Updated docs regarding front-end integration

- Removed the webpack integration. While it can be initially convenient, it tends to introduce more problems than
it solves. The repo contains an example illustrating how to implement self-mounting components which provide
similar functionality to the former webpack integration.
- Replaced the js-host dependency with an externally-managed render server.
- Added a `renderer` hook on `render_component`. Enabling you to override the default which assumes
[render-react](https://github.com/markfinger/react-render)

- Fixed a potential path issue in config files
- Replaced the webpack-service dependency with webpack-wrapper.

- Boosting render performance by using a dedicated render server.
- Added a new setting, DJANGO_REACT['RENDERER'], which is a string denoting an import path to a
callable object which returns a on object with a `render` method. By default it points to the new
render server, 'django_react.render_server.ReactRenderServer'. The legacy renderer is useable by
setting DJANGO_REACT['RENDERER'] = 'django_react.renderer.ReactRenderer'.