Add golangci-lint example

Author: sashamelentyev

README.md

@@ -6,12 +6,21 @@ A linter that detect the possibility to use variables/constants from the Go stan
 
 ## Install
 
+### `go install`
+
 ```bash
 go install github.com/sashamelentyev/usestdlibvars@latest
 ```
 
+### `golangci-lint`
+
+`usestdlibvars` is already integrated with
+[golangci-lint](https://github.com/golangci/golangci-lint).
+
 ## Usage
 
+### Binary
+
 ```console
 $ usestdlibvars -h
 usestdlibvars: A linter that detect the possibility to use variables/constants from the Go standard library.
@@ -70,6 +79,12 @@ Flags:
   -v    no effect (deprecated)
 ```
 
+### `golangci-lint`
+
+```console
+golangci-lint run --disable-all --enable usestdlibvars
+```
+
 ## Examples
 
 ```go