Fix lint script to analyze nested files

package.json

@@ -18,7 +18,7 @@
     "postpublish": "run-s release docs:json upload_docs_json",
     "release": "publish-release --assets _bundles/index.js,_bundles/index.min.js --tag $(git describe --tags) --owner 0xProject --repo 0x.js",
     "upload_docs_json": "aws s3 cp docs/index.json s3://0xjs-docs-jsons/$(git describe --tags).json --profile 0xproject --grants read=uri=http://acs.amazonaws.com/groups/global/AllUsers --content-type aplication/json",
-    "lint": "tslint src/*.ts test/*.ts",
+    "lint": "tslint src/**/*.ts test/**/*.ts",
     "test": "run-s clean test:commonjs",
     "test:umd": "./scripts/test_umd.sh",
     "test:coverage": "nyc npm run test --all",

test/utils/rpc.ts

@@ -41,7 +41,7 @@ export class RPC {
             uri: `http://${this.host}:${this.port}`,
             body: payload,
             headers: {
-                'content-type': 'application/json'
+                'content-type': 'application/json',
             },
         };
         const bodyString = await request(opts);