issue #2243 -- prefer f-strings over %-interpolation

edited docs to prefer f-strings, then str.format(), and remove %-interpolation

additional ad-hoc documentation fixes, as opportunities seen:
- replace Built-In Function (BIF) "min" variable with "mins"
- prefer BIF str(var) over "%s" % var
- reformat some code examples to clarify multiple args passed to functions
- change some single-quote strings to double-quotes for consistency
- fix mismatched parens

misc edits:
- add .vscode/ to gitignore

docs/source/Contribs/A-voice-operated-elevator-using-events.md

@@ -140,7 +140,7 @@ This is important, in order to know what variables we can use in our callback ou
 write a single line to be sure our callback is called when we expect it to:
 
 ```python
-character.msg("You just said {}.".format(message))
+character.msg(f"You just said {message}.")
 ```
 
 You can paste this line in-game, then type the `:wq` command to exit the editor and save your