[WFLY-3603] Add global resource notifications

Runtime attributes does not store their values in the resource models
and their read handler must be called before and after their write
handler to get the old and new value of the attribute.

JIRA: https://issues.jboss.org/browse/WFLY-3603
Merge pull request #62 from jmesnil/WFLY-3603_runtime_attribute-value-written_notification

[WFLY-3603] Add global resource notifications