vim-patch:7.4.832

Problem:    $HOME in `=$HOME . '/.vimrc'` is expanded too early.
Solution:   Skip over `=expr` when expanding environment names.

be83b73ddb

---

To reproduce:

```sh
nvim -u NONE -c 'e `=$HOME . "/.vimrc"`'
```

src/nvim/version.c

@@ -458,7 +458,7 @@ static int included_patches[] = {
   835,
   834,
   833,
-  // 832,
+  832,
   831,
   830,
   // 829 NA