Add wallabyjs config

Author: pimterry

wallaby.js

@@ -0,0 +1,22 @@
+export default {
+  trace: true,
+  files: [
+    'package.json',
+    'tsconfig.json',
+    'src/**/*.ts',
+    'test/**/*.ts',
+    '!test/**/*.spec.ts'
+  ],
+  tests: [
+    'test/**/*.spec.ts'
+  ],
+
+  workers: {
+    restart: true
+  },
+
+  testFramework: 'mocha',
+  env: {
+    type: 'node'
+  }
+};