Changed API to allow services to be created without the version and provider fields. Changed the Gradle and Maven plugins to remove display of the service version and provider fields.
Merge pull request #134 from scottfrederick/services

Changed API to allow services to be created without the version and provider fields
Changed Maven "cf:delete" goal and Gradle "cf-delete" task to not fail the build when attemtping to delete an app that does not exist.
Changed "versions" configuration field to "variants" in Gradle plugin.