add prettier config, and demo eslint

Author: dbouwman

.prettierignore

@@ -1,3 +1,2 @@
 package.json
 package-lock.json
-SearchQueryBuilder.ts

.prettierrc

@@ -0,0 +1,19 @@
+{
+  "arrowParens": "always",
+  "bracketSpacing": true,
+  "endOfLine": "lf",
+  "htmlWhitespaceSensitivity": "css",
+  "insertPragma": false,
+  "jsxBracketSameLine": false,
+  "jsxSingleQuote": false,
+  "printWidth": 80,
+  "proseWrap": "preserve",
+  "quoteProps": "as-needed",
+  "requirePragma": false,
+  "semi": true,
+  "singleQuote": false,
+  "tabWidth": 2,
+  "trailingComma": "es5",
+  "useTabs": false,
+  "vueIndentScriptAndStyle": false
+}

demos/.eslintrc.js

@@ -0,0 +1,13 @@
+/* eslint-env node */
+module.exports = {
+    root: true,
+    env: {
+      node: true,
+      browser: true,
+      es6: true
+    },
+    extends: [
+      'eslint:recommended',
+      'prettier',
+    ]
+  };