Merge branch 'feature/better-placeholders' into develop

src/main/jastadd/Analysis.jrag

src/main/jastadd/backend/NameResolution.jadd

src/main/jastadd/backend/Serializer.jadd

src/test/jastadd/relations/Relations.relast

src/test/jastadd/resolver/Resolver.relast

src/test/jastadd/resolver2/Resolver.relast

...test/jastadd/serializer-manual-relative/Serializer.relast

src/test/jastadd/serializer-manual/Serializer.relast

src/test/jastadd/serializer-names/Serializer.relast

src/test/jastadd/serializer-pointer/Serializer.relast

src/test/jastadd/serializer/Serializer.relast