ISIS-503: removed ObjectActionSet...

... also
- ActionType.SET
- ObjectAction#getActions()

and some unused utility classes.
ISIS-503: removed MemberLayoutArrangerUsingOrderMethod

... and also:
- SimpleOrderSet
- combined OrderSet with DeweyOrderSet
- MemberLayoutArrangerDefault
- MemberLayoutArrangerComposite
ISIS-503: removed MemberLayoutArranger completely

... inlined functionality within MemberLayoutArrangerUsingMemberOrderFacet into ObjectSpecificationDefault
ISIS-503: inlining methods, simplifying

DeweyOrderSet now acts on IdentifiedHolder, rather than FacetedMethod.
ISIS-503: more minor refactoring...

... splitting out the responsibility of converting FacetedMethods to OTOA, OTMA or ObjectActions vs traversing the DeweyOrderSet collection.
ISIS-503: DeweyOrderSet now sorting on OTOA etc ...

... rather than on FacetedMethods.
ISIS-503: more minor refactoring...

* extract/inline methods
* simplifying