[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
This shouldn't be registered here. The domain doesn't have boot errors, as it represents a multi-process entity. Only hosts have boot errors. The domain controller is just another host; it's boot errors are found in its own host=xxx tree.