Update buildinstructions.md

Correct footnote and file link

buildinstructions.md

@@ -1,5 +1,5 @@
 # Build instructions
-In general please follow the build instructions as described in [readme.md](readme.md). Here you will find a brief overview about what is needed to build your own development environment without further explanations.
+In general please follow the build instructions as described in [README.md](README.md). Here you will find a brief overview about what is needed to build your own development environment without further explanations.
 ## Setup on OS X
 ### Prerequisites
 * install python 3.10
@@ -89,5 +89,5 @@ pyinstaller --clean pronterface.spec -y
 >[!TIP] Please find further informations about building a development environment and packaging in script [release_windows.bat](release_windows.bat) where we implemented an automated build for windows.
 
 ### Remark: 
->[^1] The library **polygon3** is free for non commercial use. You can build Pronterface without this library - but then it will run slower.
->Please find further details regarding license here: https://pypi.org/project/Polygon3/
+>[^1]: The library **polygon3** is free for non commercial use. You can build Pronterface without this library - but then it will run slower.
+>Please find further details regarding license here: https://pypi.org/project/Polygon3/