Fix title/subtitle in README sample settings
Fix title/subtitle in README sample settings

`title` and `subtitle` aren't expected to be under `header`.
`assets/config.yml` shows that they are top-level keys.
My testing also confirms this.
oflannabhra/octopress-bootswatch,jilljenn/genesis-theme,oflannabhra/octopress-bootswatch,octopress/genesis-theme,octopress/genesis-theme,ludwick/fancybeans-theme,jilljenn/genesis-theme,ludwick/fancybeans-theme