Background
Developer UI is a legacy way for Kimchi to render html page to the front
end. And the font end can display the html page directly without
creating the page dynamically. After the design UI code went into
Kimchi, developer UI is attracting less and less attention and have been
broken for a while. Further, design UI is good enough and can replace
the developer UI without any encumbrance. Maintaining two sets of UI
brings a lot of extra works and is unnecessary. So it is reasonable to
remove the design UI code from Kimchi repository.
Work to be done:
* Remove the code to support rendering html text in controller
* Remove the code to generate html page from the cheetah template