neovim/neovim — pull request #530 by mhinz (2014-04-14 12:29:22+00:00)
Title: [RFC] vim-patch:7.4.233

```
Problem: Escaping special characters for using "%" with a shell command
is inconsistant: parentheses are escaped but spaces are not.

Solution: Only escape "!". (Gary Johnson)
```

https://code.google.com/p/vim/source/detail?r=22a1d5762ba3a75984e89dcc47a65498f63a6c2c