Adjust code to airbnb style guide, including eslint rules and prettier configuration for code base

.prettierrc.js

@@ -0,0 +1,16 @@
+module.exports = {
+  endOfLine: 'lf',
+  printWidth: 100,
+  semi: true,
+  singleQuote: true,
+  tabWidth: 2,
+  trailingComma: 'none',
+  overrides: [
+    {
+      files: '*.js, *.jsx',
+      options: {
+        trailingComma: 'all' // or es5
+      }
+    }
+  ]
+};