message: Move assets package to optional deps
diff: "tslib": "^1.9.0",
  "winston": "^3.1.0"
  },
  + "optionalDependencies": {
  + "@flogo-web/client-assets": "file:./libs/client-assets"
  + },
  "devDependencies": {
  - "@flogo-web/client-assets": "file:./libs/client-assets",
  "@angular-devkit/build-angular": "~0.11.0",
  "@angular-devkit/build-ng-packagr": "~0.11.0",
  "@angular/animations": "~7.1.1",
  