One image in README.md is down
# Problems summary
There is a broken image in `README.md`, `![Markdown](http://i2.kiimg.com/1949/c18404d7afdc7f3a.gif)` this one is broken.

## Expected
The image is not broken.

## Environment Information
 * OS: Linux
 * vim version: 8.?
 * neovim version: v0.2.2


## The reproduce ways from Vim starting (Required!)
Not really need vim to see this.


## Screenshot (if possible)
It's in the `README.md`

## Upload the log messages by `:redir` and `:message`
No log