Deprecate memento.customFields

- and remove from policy/enricher rebind support
Policy/enricher rebind: set config
Fix typo in comment
Adds RebindLocationTest.testResoresConfig
Remove FIXMEs about policy/enricher persistence being disabled
Policy/enricher rebind: use config

- use “config” instead of “flags”
- use no-arg constructor where available
- adds ManagementContextInternal.getPolicyFactory()
- refactor InternalPolicyFactory to be more like InternalLocationFactory
XmlMementoSerializerTest tidy
Tidy persistence TODO comments
Merge pull request #1417 from aledsage/feature/policy-enricher-mement-incorporate-comments

policy enricher memento: incorporate comments