[RFC] vim-patch:7.4.215

```
Problem:  Inconsistency: ":sp foo" does not reload "foo", unless "foo"
          is the current buffer. (Liang Li)

Solution: Do not reload the current buffer on a split command.
```
https://code.google.com/p/vim/source/detail?r=f069a3a0f84451aa498c6c22d8f922d1e695e96d

Accompanying patch to https://github.com/neovim/neovim/pull/524