[Formatting] Make Host NonNullByDefault.
Added interface LocallyIdentifiable.
Role: Sped up and improved permissions checking algorithm.
Role: Added more getters and permission check methods.
Improved MonetaryValue printing: Fixed a bug and added separators.
IdMapper's unity mapper doesn't map to null, but to the given value.
Less redundant Payment method names.
Update actions for LocallyIdentifiable and Payment changes.