heist.cabal: allow transformers-0.5, process-1.4, time-1.6 (ghc-8)
heist.cabal: allow transformers-0.5, process-1.4, time-1.6 (ghc-8)

Signed-off-by: Sergei Trofimovich <df7d2cee2e7ececeb2368216a0f9d0537fd32149@google.com>

snapframework/heist,sopvop/heist