patch fc61c479431701d950370effa02a254d40516bc8
Author: Guillaume Hoffmann <guillaumh@gmail.com>
Date: Wed Mar 28 15:08:06 -03 2018
* no longer read old cache location
We stopped writing in .darcs/cache two releases ago, and
"darcs optimize cache" provided the way to migrate these cached files.
BTW. We really should make it possible for users to limit how much disk
space the cache uses, accompanied by some useful expiration policy (such
as "least recently used").