lang: Add debug flag and Logf to fact init struct

lang/funcs/facts/facts.go

@@ -68,6 +68,8 @@ type Init struct {
 	//Noop bool
 	Output chan types.Value // Stream must close `output` chan
 	World  engine.World
+	Debug  bool
+	Logf   func(format string, v ...interface{})
 }
 
 // Fact is the interface that any valid fact must fulfill. It is very simple,

lang/funcs/facts/func.go

@@ -62,6 +62,8 @@ func (obj *FactFunc) Init(init *interfaces.Init) error {
 			Hostname: init.Hostname,
 			Output:   init.Output,
 			World:    init.World,
+			Debug:    init.Debug,
+			Logf:     init.Logf,
 		},
 	)
 }