This makes it possible for encoders to output better representation
of the actual objects instead of working with chopped up segments.
* IAnsiConsole.Write now takes an IRenderable instead of segments
* Calculating cell width does no longer require a render context
* Removed RenderContext.LegacyConsole
* Removed RenderContext.Encoding
* Added Capabilities.Unicode
This commit adds support for recording console output
as well as exporting it to either text or HTML. A user can
also provide their own encoder if they wish.