After one too many pipeline failures due to old spell-checking
mistakes, I decided to own up to my stuff and spell check
everything. I actually ran:

     codespell --interactive 3 --write-changes *

And dealt with *almost* all the errors, except stuff in old/ which
I'll remove shortly.

When an error comes up now, it is new and should be fixed.

policy/tpa-rfc-2-support.md

@@ -14,7 +14,7 @@ support levels.
 It is important to define how users get help from, what is an
 emergency for, and what is supported by the sysadmin team (AKA
 "TPA"). So far, only the former has been defined, rather informally,
-but has yet to be collectively agreed withing the larger team.
+but has yet to be collectively agreed within the larger team.
 
 This proposal aims to document the current situation and propose new
 support levels and a support policy that will provide clear guidelines