add max_lifetime value and default to 60
Merge branch 'develop' into feature/issue-774-metrics-mw-expire-keys
expire + test
using setex
Fix middleware test assertion.
Merge branch 'feature/issue-774-metrics-mw-expire-keys' into develop
Merge branch 'develop' of github.com:praekelt/vumi-go into develop
Merge branch 'develop' of github.com:praekelt/vumi-go into develop
Merge branch 'develop' into feature/issue-779-fix-billing-account-unicode-implementation