Refactored junit TaskTests into spock TaskSpec
Refactored junit UserContextTests into spock UserContextSpec
Enabled parsing of a UserContext json blob by Jackson
Refactored junit RegionTests into spock RegionSpec
Added missing GroovyDoc comments to Region
Enabled Jackson serialization and deserialization of Region objects with backward compatibility.

Jackson will now serialize Region objects code values like "us-east-1". Jackson will deserialize Region objects from either code values like "us-east-1" or enum names like "US_EAST_1". This means the existing JSON blobs in SWF workflow execution tags can still be deserialized, and so can the preferred newer style of deserialized blob that use AWS region codes instead of enum names.
ServerService unused import
deserialization of Region more
UserContext doesn't need JsonProperty annotations
Omitted closure fields from toString of EntityType, for easier comparisons in unit test failures
Added method to create a Task from a JSON blob
Omitted non-field getters from Jackson serialization on Task
Added a return type to clarify a method's usage
Added a unit test for round-trip serialization and deserialization of a list of Task objects.
serverservicespec codenarc
taskspec codenarc
Removed unnecessary toJson method
RegionSpec test rename
UserContextSpec test rename
Declare shared ObjectMapper spring bean