Return content language in API calls

Within the Gist API, the language is returned for each file. It would be great to have the language returned when querying repository content as well.

For example

curl \
  -H "Accept: application/vnd.github.v3+json" \
  https://api.github.com/repos/octocat/hello-world/contents/PATH

would return

{
  "type": "file",
  "encoding": "base64",
  "size": 5362,
  "name": "README.md",
  "path": "README.md",
  "content": "encoded content ...",
  "language": "markdown",
  "sha": "3d21ec53a331a6f037a91c368710b99387d012c1",
  "url": "https://api.github.com/repos/octokit/octokit.rb/contents/README.md",
  "git_url": "https://api.github.com/repos/octokit/octokit.rb/git/blobs/3d21ec53a331a6f037a91c368710b99387d012c1",
  "html_url": "https://github.com/octokit/octokit.rb/blob/35d968fddf43f8cd7618e082e17e958be67964f1/README.md",
  "download_url": "https://raw.githubusercontent.com/octokit/octokit.rb/master/README.md",
  "_links": {
    "git": "https://api.github.com/repos/octokit/octokit.rb/git/blobs/3d21ec53a331a6f037a91c368710b99387d012c1",
    "self": "https://api.github.com/repos/octokit/octokit.rb/contents/README.md",
    "html": "https://github.com/octokit/octokit.rb/blob/35d968fddf43f8cd7618e082e17e958be67964f1/README.md"
  }
}