Found via `codespell -q 3 -S *.po,./po,*.min.js,./ChangeLog*,./NEWS,./borrowed,./doc/README*,./AUTHORS,./libgnucash/tax/us/txf-de*,./data/accounts -L ans,ba,cas,dragable,gae,iff,iif,mut,nd,numer,parm,parms,startd,stoll`
- rename example files to this extension
- replace references to the old extension where appropriate
git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@19319 57a11ea4-9604-0410-9ed3-97b8803252fd