Add python libraries on Backend Roadmap

Added some famous python libraries.
- Basic data analysis : Tensorflow, Pandas, NumPy, SciPy, Scikit-learn 
- Web crawling : Beautiful Soup, Scrapy

README.md

@@ -25,7 +25,7 @@ If you think that these can be improved in anyway, please do suggest.
 
 For the backend, personally I would prefer Node JS and PHP-7 for the full time plus I have been experimenting lately with Go and I quite like it. Apart from these, if I have to choose another one, I would go for Ruby. However this is just my personal preference, you can choose any of the shown languages and you will be good.
 
-![](https://i.imgur.com/bAmwJMr.png)
+![](http://i.imgur.com/jQdqLgH.png)
 
 ## 👷 DevOps Roadmap