Sublime Text Theme: Completions for "extended" themes #239
Description
The Sublime Text Theme format supports the "extends" directive to extend existing themes.
The auto completions suggest variables from the open sublime-theme file only. They should also include variables from the extended base theme.
If the base theme is open in another view, the existing self.view.find_by_selector() strategy can be used to keep the auto-completions up to date. Otherwise the base theme needs to be opened via loade_resource to extract the variables.