Use "construct" instead of "this" to define constructors.

builtin/core.wren

@@ -103,7 +103,7 @@ class Sequence {
 }
 
 class MapSequence is Sequence {
-  this new(sequence, fn) {
+  construct new(sequence, fn) {
     _sequence = sequence
     _fn = fn
   }
@@ -113,7 +113,7 @@ class MapSequence is Sequence {
 }
 
 class WhereSequence is Sequence {
-  this new(sequence, fn) {
+  construct new(sequence, fn) {
     _sequence = sequence
     _fn = fn
   }
@@ -133,7 +133,7 @@ class String is Sequence {
 }
 
 class StringByteSequence is Sequence {
-  this new(string) {
+  construct new(string) {
     _string = string
   }
 
@@ -180,7 +180,7 @@ class Map {
 }
 
 class MapKeySequence is Sequence {
-  this new(map) {
+  construct new(map) {
     _map = map
   }
 
@@ -189,7 +189,7 @@ class MapKeySequence is Sequence {
 }
 
 class MapValueSequence is Sequence {
-  this new(map) {
+  construct new(map) {
     _map = map
   }