[nongnu] elpa/rust-mode 2921159: mention NonGNU ELPA

[ELPA Syncer]

branch: elpa/rust-mode
commit 29211595d7f896fd1f86608757020249fc66924b
Author: brotzeit <brotzeitmacher@gmail.com>
Commit: brotzeit <brotzeitmacher@gmail.com>

    mention NonGNU ELPA
    
    close #411
---
 README.md | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/README.md b/README.md
index 16ebf41..324de96 100644
--- a/README.md
+++ b/README.md
@@ -78,6 +78,14 @@ And put this in your config to load rust-mode automatically:
 
 `(require 'rust-mode)`
 
+### NonGNU ELPA
+
+https://elpa.nongnu.org/
+
+``` elisp
+(with-eval-after-load 'package (add-to-list 'package-archives '("nongnu" . 
"https://elpa.nongnu.org/nongnu/";)))
+```
+
 ### Manual installation
 
 Clone this repository locally, and add this to your init.el: