Fix heading level of 'Try' section

It was agreed to be '## Try:' but there were many files where it was
'### Try:'. This has been corrected.

2020/tsoj/README.md

@@ -16,7 +16,7 @@ to those familiar with vi. See [Alternate code](#alternate-code) below.
 ```
 
 
-### Try:
+## Try:
 
 ```sh
 # Make your terminal as large as possible, possibly reduce your font size