improving incremental compilation

support lazy arguments in data type generator
SafeLazy implementation that explicitly clears the reference to the thunk
in API representation, drop synthetic modifier and merge deferred into abstract
handle cyclic structures in API generation, display, comparison, persistence
gzip compile cache file
bump to 2.8.1.RC3, project definition cleanup
fix main method detection to check for the right name
properly view inherited definitions
exclude constructors of ancestors

interface/type

@@ -3,7 +3,7 @@ Type
 	SimpleType
 		Projection
 			prefix : SimpleType
-			id : String
+			id: String
 		ParameterRef
 			id: Int
 		Singleton
@@ -16,9 +16,9 @@ Type
 		baseType : SimpleType
 		annotations : Annotation*
 	Structure
-		parents : Type*
-		declared: Definition*
-		inherited: Definition*
+		parents : ~Type*
+		declared: ~Definition*
+		inherited: ~Definition*
 	Existential
 		baseType : Type
 		clause: TypeParameter*