According to npm coding style, config keys are separated by dashes, not underscores.
The point is: if this feature will ever make it into upstream, config key will be named according to that standard. If that happens, I wouldn't want people to change their configs everywhere...
PS: also added some docs, I know nobody cares, but test/tap/config-meta.js fails :P
rename "github_token" to "github-token"