devel/hs-retry: import hs-retry-0.9.1.0

This package exposes combinators that can wrap arbitrary monadic
actions. They run the action and potentially retry running it with some
configurable delay for a configurable number of times. The purpose is to
make it easier to work with IO and especially network IO actions that often
experience temporary failure and warrant retrying of the original
action. For example, a database query may time out for a while, in which
case we should hang back for a bit and retry the query instead of simply
raising an exception.

(pho)