removed mention of Py2 from release footer

build/release_footer.md

@@ -3,5 +3,5 @@ This release saves `${graph_version}` graphs.
 This release includes backwards compatibility for graph versions as old as `0.45` .
 
 # Pip Installation
-From a Python(2 or 3) environment run the following command:  
+From a Python 3 environment run the following command:  
 `pip install nxt-core`