Use strict for build scripts

Author: cvle

.eslintrc.yml

@@ -1,8 +1,9 @@
 extends:
   - airbnb-base
 env:
-  es6: true
   node: true
+parserOptions:
+  sourceType: script
 rules:
   # sometimes brackets are useful for formatting.
   arrow-body-style: 0

gulpfile.js

@@ -1,3 +1,5 @@
+"use strict";
+
 const gulp = require("gulp");
 const ts = require("gulp-typescript");
 const tslint = require("gulp-tslint");

karma.conf.js

@@ -1,3 +1,5 @@
+"use strict";
+
 const path = require("path");
 
 module.exports = (config) => {

tests.webpack.js

@@ -1,2 +1,4 @@
+"use strict";
+
 const integrationContext = require.context("./test", true, /\.tsx?$/);
 integrationContext.keys().forEach(integrationContext);

webpack.config.js

@@ -1,4 +1,4 @@
-
+"use strict";
 
 const fs = require("fs");
 const webpack = require("webpack");