XD-1089 Add shell command for job executions

* Add `job execution list` command
* Add `job execution display` command
* Add numerous Jackson MixIns + Deserializer to ensure deserialization of Batch objects
* Add tests
* Shell: Add Table#addRow() helper method (plus test)
* Add helper method CommonUtils#getUtcTime()

Jira: https://jira.springsource.org/browse/XD-1089

XD-1089 Fix slf4j version conflict

* exclude group 'org.slf4j' from dependency `spring-batch-admin-manager` in module `spring-xd-rest-domain`

Cleanup needed