Improve text formatting

Author: vecxoz

PY2.md

@@ -16,7 +16,8 @@ NOTE. It will require legacy versions of the following packages:
 * numpy<1.17
 * scipy<1.3
 * scikit-learn>=0.18,<0.21
+
 There is a dedicated branch on GitHub called `py2` with appropriate requirements in `setup.py`.  
 Installation:  
 
-`pip install https://github.com/vecxoz/vecstack/archive/py2.zip`
+`pip install https://github.com/vecxoz/vecstack/archive/py2.zip`