[js][bonus-02_explicit_method] Add base

Author: rgomezcasas

examples/js/js-bonus-02_explicit_method/.gitignore

@@ -0,0 +1,2 @@
+node_modules/
+.tmp/

examples/js/js-bonus-02_explicit_method/babel.config.json

@@ -0,0 +1,4 @@
+{
+    "presets": ["@babel/preset-env"],
+    "plugins": ["@babel/plugin-proposal-class-properties"]
+}

examples/js/js-bonus-02_explicit_method/jest.config.js

@@ -0,0 +1,8 @@
+module.exports = {
+    testEnvironment: 'node',
+    verbose: true,
+    cacheDirectory: './.tmp/jestCache',
+    transform: {'^.+\\.js$': 'babel-jest'},
+    testMatch:[ "**/tests/**/*.[jt]s?(x)", "**/?(*.)+(spec|test).[jt]s?(x)" ],
+    moduleFileExtensions: ['js']
+};