rails/sprockets-rails — pull request #127 by matthewd (2014-04-09 16:57:44+00:00)
Title: Version the gem's helpers; if they change, the cache must go

Use an explicit constant, so we don't invalidate caches for every minor
bump of the gem... but we can do so when the need arises.

Adding this value obviously counts as a bump & invalidation: that's
desirable, so #126 can start from a clean slate.