* Sync Spock dependency versions
* Now that Spock no longer depends on 'groovy-all', for the database test it was
necessary to add 'groovy-sql'.
* Make feature method names friendlier in unrolled DatabaseDrivenSpec
* Make IncludeExcludeExtensionSpec print messages
This way the user can verify visually that in-/excludes actually work as
expected.
* Upgrade Groovy 2.5.12 -> 2.5.13
* Slightly adjust README.adoc
Change passive style "all feedback is appreciated" to active style "we
appreciate all feedback".