Add lock for security fixes (#31)

Author: jarhill0

README.md

@@ -25,6 +25,7 @@ Initial Commit | [🎉 Party Popper](http://emojipedia.org/party-popper/)
 Version Tag | [🔖 Bookmark](http://emojipedia.org/bookmark/)
 New Feature | [✨ Sparkles](http://emojipedia.org/sparkles/)
 Bugfix | [🐛 Bug](http://emojipedia.org/bug/)
+Security Fix | [🔒 Lock](https://emojipedia.org/lock/)
 Metadata | [📇 Card Index](http://emojipedia.org/card-index/)
 Refactoring | [♻️ Black Universal Recycling Symbol](http://emojipedia.org/black-universal-recycling-symbol/)
 Documentation | [📚 Books](http://emojipedia.org/books/)