upgrade packages. disable yarn.lock in favor of package-lock being the single source of truth.

.gitignore

@@ -15,4 +15,6 @@ node_modules
 coverage
 test/uploads
 example/uploads/*
-!example/uploads/placeholder.txt
+!example/uploads/placeholder.txt
+
+yarn.lock

package.json

@@ -31,12 +31,12 @@
   "repository": "richardgirges/express-fileupload",
   "devDependencies": {
     "body-parser": "^1.18.3",
-    "coveralls": "^3.0.1",
-    "eslint": "^4.5.0",
+    "coveralls": "^3.0.2",
+    "eslint": "^5.6.0",
     "express": "^4.16.3",
     "istanbul": "^0.4.5",
-    "mocha": "^3.5.0",
+    "mocha": "^5.2.0",
     "rimraf": "^2.6.2",
-    "supertest": "^3.0.0"
+    "supertest": "^3.3.0"
   }
 }