Add github config

ofborg/src/config.rs

@@ -11,6 +11,7 @@ pub struct Config {
     pub checkout: CheckoutConfig,
     pub nix: NixConfig,
     pub rabbitmq: RabbitMQConfig,
+    pub github: Option<GithubConfig>,
 }
 
 #[derive(Serialize, Deserialize, Debug)]
@@ -27,6 +28,12 @@ pub struct NixConfig {
     pub remote: String,
 }
 
+
+#[derive(Serialize, Deserialize, Debug, Clone)]
+pub struct GithubConfig {
+    pub token: String,
+}
+
 #[derive(Serialize, Deserialize, Debug)]
 pub struct RunnerConfig {
     pub identity: String,