[WFLY-543] : Provide an operation to request service status report after server has been started

Adding the new command "read-boot-errors" available from core-service=management to list all operations that failed during boot.
It displays all boot errors with the failed operation and the failure description / exception of the error.
Jira: https://issues.jboss.org/browse/WFLY-543
Ok, please file a subtask on this JIRA to:

1) Change ParseAndMarshalModelsTestCase to use the new ones and then remove the old ones once that's done.

2) Add something to wildfly-core/testsuite-core/shared to support ParseAndMarshalModelsTestCase. It's using too much stuff that should be internal to wildfly-core.