Initial support for cluster mode

* support using only one unique server node for a quartz scheduled job
* require a server uuid for cluster mode
Use serverUUID for scheduled jobs

* set serverNodeUUID when saving scheduled jobs
* unschedule from quartz if uuid does not match
Validate serverNodeUUID in domain classes
Set serverNodeUUID for new executions

* store the UUID of cluster node in executions
Remove unused code
Update UI to indicate cluster scheduled times

* show correct schedule time if running on a different cluster node
* indicate the job is expected to run
Cleanup bootstrap code
Update API version to 7
Add /incubator api endpoint for schedule takeover

* path /incubator/jobs/takeoverSchedule
* PUT content identifies server UUID to takeover
* response indicates how many jobs were successfully taken over or not
* response includes job identifiers
* supports json/xml
* requires 'admin' authorization for resource kind 'job' at the
  application context
Add documentation for schedule takeover api
Add test for ExecutionService.cleanupRunningJobs
test ExecutionService.claimScheduledJobs
Change FrameworkService properties to method calls

* for test mocking/override
Test jobs receive current cluster server UUID on edit
Add registerMetaClass to test
Merge pull request #396 from gschueler/feature/cluster-mode-unique-server-for-job-schedules

Feature/cluster mode unique server for job schedules