Add AUR support documents

[GitHub #57 #16]

pkg/README.md

@@ -4,7 +4,7 @@ https://github.com/RubyMetric/chsrc/issues/16
 
 - [x] `Homebrew`
 - [x] `Scoop`
-- [ ] `AUR`
+- [x] `AUR`
 - [ ] `Flatpak`
 - [ ] ...
 
@@ -12,6 +12,9 @@ https://github.com/RubyMetric/chsrc/issues/16
 $ brew install chsrc
 
 $ scoop install chsrc
+
+$ yay -S chsrc # binary from release
+$ yay -S chsrc-git # build from source
 ```
 
 <br>
@@ -24,3 +27,9 @@ https://github.com/Homebrew/homebrew-core/blob/master/Formula/c/chsrc.rb
 # Scoop
 
 https://github.com/ScoopInstaller/Main/blob/master/bucket/chsrc.json
+
+# AUR
+
+[chsrc](https://aur.archlinux.org/packages/chsrc-git)：从release打包的稳定发布版本
+
+[chsrc-git](https://aur.archlinux.org/packages/chsrc-git)：从最新源码构建的版本，可能不稳定