Add lsp-mode links (#2260)

* Add lsp-haskell links

* Correct plugin url

Co-authored-by: Michael Peyton Jones <me@michaelpj.com>

* Correct plugin url

Co-authored-by: Michael Peyton Jones <me@michaelpj.com>

Co-authored-by: Michael Peyton Jones <me@michaelpj.com>

docs/configuration.md

@@ -21,14 +21,14 @@ For example, there are protocol methods for highlighting matching identifiers th
 This is a capability which any server can implement, so the client can decide generically whether to ask the server to do it or not.
 So your editor can provide a setting to turn this on or off globally, for any language server you might use.
 
-Settings like this are typically provided by the generic LSP client support for your editor, for example in Emacs by `lsp-mode`.
+Settings like this are typically provided by the generic LSP client support for your editor, for example in Emacs by [`lsp-mode`](https://github.com/emacs-lsp/lsp-mode).
 
 ### Generic editor options
 
 Your editor may provide some settings that affect how the information from the language server is used.
 For example, whether popups are shown, or whether code lenses appear by default.
 
-Settings like this are typically provided by the generic LSP client support for your editor, for example in Emacs by `lsp-mode`.
+Settings like this are typically provided by the generic LSP client support for your editor, for example in Emacs by [`lsp-mode`](https://github.com/emacs-lsp/lsp-mode).
 
 ### Language-specific server options