Adds rendering module's readme and links from global readme.
Fixes typo in rendering module's readme.
Updates readme to mention render-handlers by object-key.
Adds Render mediator and, RendererInterface and AbstractRenderer.
Updates composer.json to require smarty.
Adds MustacheHandler and updates AbstractHandler.
Adds merge option to setRenderArgs in AbstractHandler.
Adds JsonHandler.
Updates renderers' render() to take  param.
Adds HtmlHandler and renames JsonHandler.
Fixes class name typo of Renderer.
Updates readme to include HtmlHandler.
Adds getExtention to AbstractHandler and inits handlers with config.
Adds documentation for all classes/interfaces.
Updates rendering handlers to take more responsibilities.
Adds trait RendererController as compatibility fallback.
Updates modules' controllers to use RendererController trait.
Changes config structure and removes default/additionals.
Adds documentation where still necessary.
Adds initial test confugration and a set of basic tests.