New section - Setup the environment

Author: Adi Chirilov

README.md

@@ -1,5 +1,7 @@
 # Flask - Learn by coding
-Simple Flask tutorial for beginners.
+A simple [Flask](http://flask.pocoo.org/) tutorial for beginners.
 
 ## Content
-- The [source code](/src) 
+ - The [source code](/src)
+ - [Setup the environment](https://docs.appseed.us/tutorials/flask-learn-by-coding/flask-setup-python-environment/) - download [Python](https://www.python.org/), check the installation via command `python --version` and install Flask `pip install Flask`
+