list function has been added

src/main/java/serene/simple/RootScope.java

@@ -45,6 +45,7 @@ public class RootScope extends AScope {
       put("not", new NotFn());
       put("conj", new ConjFn());
       put("list", new ListFn());
+      put("first", new FirstFn());
       // put("let", new LetFn());
       // put("cond", new CondFn());
       //put("reduce", new ReduceFn());

src/main/java/serene/simple/builtin/ListFn.java

@@ -21,7 +21,6 @@ package serene.simple.builtin;
 
 import java.util.ArrayList;
 import java.util.Collections;
-import java.util.List;
 
 import serene.simple.IScope;
 import serene.simple.ListNode;