XD-1281 Create Better UI instead of Boot's default "Whitelabel Error Page"

* Add static 404 page modeled after spring.io
* Add ErrorHandler, extending `org.springframework.boot.actuate.web.BasicErrorController`
  - redirect 404 statuses to static page
Fix compiler error on using java 1.6
XD-1676 FileJdbc Acceptance Test
Checks if stream or job is reported as deployed.
XD-1680 JdbcHdfs Job Acceptance Tests