tools: add reference to vis-lspc to README.md

Change-Id: Iee27c4b0cffaccaf4116782ddde5ed7be933754c
Signed-off-by: Matěj Cepl <[email protected]>

Author: mcepl

gopls/README.md

@@ -31,6 +31,7 @@ TODO: also, be more consistent about editor (e.g. Emacs) vs. client (e.g. eglot)
 * [Atom](https://github.com/MordFustang21/ide-gopls)
 * [Sublime Text](doc/subl.md)
 * [Acme](https://github.com/fhs/acme-lsp)
+* [Vis](https://gitlab.com/muhq/vis-lspc)
 * [Lapce](https://github.com/lapce-community/lapce-go)
 
 If you use `gopls` with an editor that is not on this list, please send us a CL