Merge pull request #754 from resin-io/753-legacy-image

fix: Don't assume config is defined for legacy images in logger

src/config.ts

@@ -195,7 +195,8 @@ class Config extends EventEmitter {
 				return setImmediate(() => {
 					this.emit('change', keyValues);
 				});
-			});
+			})
+			.return();
 	}
 
 	public remove(key: string): Bluebird<void> {

src/logger.ts

@@ -259,6 +259,7 @@ export class Logger {
 		}
 		if (eventObj.service != null &&
 			eventObj.service.serviceName != null &&
+			eventObj.service.config != null &&
 			eventObj.service.config.image != null
 		) {
 			return `${eventObj.service.serviceName} ${eventObj.service.config.image}`;