Add gradient service

projects/common/src/fm/common-service.module.ts

@@ -35,6 +35,7 @@ import { PackageService } from './services/package.service';
 import { PackagePreloadStrategy } from './services/package-preload-strategy.service';
 import { SenmlService } from './services/senml-service';
 import { DeviceService } from './services/device.service';
+import { GradientService} from './services/gradient.service';
 
 export {
   FolderService,
@@ -61,7 +62,8 @@ export {
   PackageService,
   SenmlService,
   PackagePreloadStrategy,
-  DeviceService
+  DeviceService,
+  GradientService
 };
 
 @NgModule({