Merge branch 'hotfix/0.7.1'
Expose setex if exists and is a function

This allows us to use the cache store with a ttl on some transactions,
but not all.
Merge pull request #7 from evanlucas/feature/setex

Expose setex if exists and is a function
unit test for setex()
Merge branch 'master' into develop
0.8.0 release notes
Merge branch 'release/0.8.0' into develop