switch to tasty framework, and allow QuickCheck-2.7

(cherry picked from commit a6ad2ac058a4bac77bfe24d7491eb785743aba2d)
travis: build with ghc-7.8.1

(cherry picked from commit a6124b84f455f1f0fc42af0d7d74c43680c22ac7)
Bump version to 0.2.2.5
Release notes for 0.2.2.5

(cherry picked from commit d944eac5f411bcb5eed69cf4f6b63dcb336fda4e)