BREAKING CHANGE: omnisharp-emacs is being removed as it is no longer
maintained and was deprecated (see
https://github.com/OmniSharp/omnisharp-emacs) in favor of the
omnisharp-roslyn LSP clients. It also no longer works in Emacs
28 (throwing an error when starting the server). Users need only enable
:lang (csharp +lsp) and install omnisharp-roslyn instead.
The :lang csharp module's README.org was intentionally left un-updated
because of a larger, upcoming documentation update which will reflect
these changes.
Close#5036