etaremune – Reverse-counting enumerate environment

The pack­age im­ple­ments the etare­mune en­vi­ron­ment which is an enu­mer­ate en­vi­ron­ment in which the la­bels de­crease in­stead of in­creas­ing.
The pack­age is no­tice­ably more ef­fi­cient than the revnum pack­age, which uses painfully many coun­ters.