Added Levels FYI

Author: mr-mig

README.md

@@ -136,6 +136,8 @@ But knowing the stuff will help you become better! :muscle:*
 - :book: [Site Reliability Engineering](https://landing.google.com/sre/sre-book/toc/index.html)
 
 ### Career
+- :moneybag: [Levels FYI](https://www.levels.fyi)  
+  Salary stats for various tech companies. Better than Glassdoor. 
 - :page_facing_up: [10 Things Every Programmer Should Know For Their First Job](http://www.applematters.com/article/10-things-every-programmer-should-know-for-their-first-job/)
 - :page_facing_up: [How Much Do Software Engineers Really Make in Each City?](https://www.codementor.io/blog/best-cities-software-engineer-earnings-271vpf599k)
 - :page_facing_up: [Software Engineers Tenure in San Francisco](https://hackerlife.co/blog/san-francisco-large-corporation-employee-tenure)