Request to support render a GitHub id to be a link

Sometimes, we might want to show a link in a README file. For example, my GitHub ID is `linuxsuren`. If I want to have a link of it, we need to add the following text:

```markdown
[linuxsuren](https://github.com/linuxsuren]
```

Actually, we can try to call the GitHub API to determine if this string is a GitHub (or Twitter) ID. Make it be a link if it's.