feat(prefixed-attributes): added highlighting for let- and ref prefix

Added syntax highlighting for let-prefix and differentiated from ref-prefix

README.md

@@ -6,6 +6,7 @@
 [![Build status](https://travis-ci.org/ghaschel/vscode-angular-html.svg?branch=master)](https://travis-ci.org/ghaschel/vscode-angular-html.svg?branch=master)
 [![Installs](https://vsmarketplacebadge.apphb.com/installs-short/ghaschel.vscode-angular-html.svg?style=flat&color=blue)](https://marketplace.visualstudio.com/items?itemName=ghaschel.vscode-angular-html)
 [![Version](https://vsmarketplacebadge.apphb.com/version-short/ghaschel.vscode-angular-html.svg?style=flat&color=blue)](https://marketplace.visualstudio.com/items?itemName=ghaschel.vscode-angular-html) [![Greenkeeper badge](https://badges.greenkeeper.io/ghaschel/vscode-angular-html.svg)](https://greenkeeper.io/)
+[![Commitizen friendly](https://img.shields.io/badge/commitizen-friendly-brightgreen.svg)](http://commitizen.github.io/cz-cli/)
 
 <div align="center">
     <img src="https://raw.githubusercontent.com/ghaschel/vscode-angular-html/master/assets/angular-html.png" title="vscode-angular-html" alt="Logo" />

commitlint.config.js

@@ -0,0 +1,10 @@
+module.exports = {
+  extends: ['@commitlint/config-conventional'],
+  rules: {
+    'type-enum': [
+      2,
+      'always',
+      ['build', 'chore', 'ci', 'docs', 'feat', 'fix', 'improvement', 'perf', 'refactor', 'revert', 'style', 'test'],
+    ],
+  },
+};