This change removes the Spring Cloud Task dependency upon a
CommandLineRunner from boot and moves the handling of the task lifecycle
closer to the "edge" of a Spring Boot application.
With this change, now a developer simply adds @EnableTask to their
configuration somewhere and the task lifecycle will be recorded.
Resolvesspring-cloud/spring-cloud-task#39
* `DefaultTaskConfigurer` returns only one `SimpleTaskRepository` all others have been removed
* `SimpleTaskRepository` can use `JdbcTaskExecutionDao` or a `MapTaskExecutionDao`
* Add `Jdbc` and Map` `TaskRepositoryFactoryBeans` to support the creation of the correct type of `SimpleTaskRepository`
* `TaskDatabaseInitializer` will initialize a database if a datasource is found and if they have not disabled it using the `spring.task.initialize.enable`
* Add tests
* Added Transaction Support
* Re-add the samples to `pom.xml`
* Samples pom skips install and deploy lifecycle targets.
