feat: update cheat sheet + added source file (#711)

Co-authored-by: Weyert de Boer <[email protected]>

Author: weyert

other/cheat-sheet.pdf

@@ -0,0 +1,13 @@
+# Cheat sheet design
+
+The cheat sheet document has been created using the desktop publishing software called Affinity Publisher, the original source file can be found in this folder
+
+## Fonts used
+
+- Menlo
+- Arial
+
+## Standard distances
+
+15pt between boxes
+8pt margin from box edge to inner text