[release-branch.go1.2] misc/vim: describe how to get gofmt-on-save behaviour.

««« CL 31770043 / 286f0ddb799b
misc/vim: describe how to get gofmt-on-save behaviour.

Fixes #6826.

R=golang-dev, bradfitz, adg
CC=golang-dev
https://golang.org/cl/31770043
»»»

R=golang-dev
CC=golang-dev
https://golang.org/cl/34960043
diff --git a/misc/vim/readme.txt b/misc/vim/readme.txt
index a394cec..b8469f9 100644
--- a/misc/vim/readme.txt
+++ b/misc/vim/readme.txt
@@ -14,6 +14,11 @@
 If you want to select fewer plugins, use the instructions in the rest of
 this file.
 
+A popular configuration is to gofmt Go source files when they are saved.
+To do that, add this line to the end of your $HOME/.vimrc.
+
+  autocmd FileType go autocmd BufWritePre <buffer> Fmt
+
 
 Vim syntax highlighting
 -----------------------