Add toChain() for object and array builder.

Author: javadev

src/main/java/com/github/underscore/lodash/U.java

@@ -2621,6 +2621,10 @@ public static Builder fromJson(final String json) {
             return builder;
         }
 
+        public Chain<Object> toChain() {
+            return new U.Chain<>(data.entrySet());
+        }
+
         @Override
         public String toString() {
             return data.toString();
@@ -2692,6 +2696,10 @@ public static ArrayBuilder fromJson(final String json) {
             return builder;
         }
 
+        public Chain<Object> toChain() {
+            return new U.Chain<>(data);
+        }
+
         @Override
         public String toString() {
             return data.toString();

src/test/java/com/github/underscore/lodash/LodashTest.java

@@ -900,6 +900,7 @@ public void objectBuilder() {
         assertEquals("{}", builder.build().toString());
         builder.clear();
         assertEquals("{}", builder.build().toString());
+        builder.toChain();
         Map<String, Object> value = U.objectBuilder()
             .add("firstName", "John")
             .add("lastName", "Smith")
@@ -937,6 +938,7 @@ public void arrayBuilder() {
         assertEquals("[1, 1, 2]", builder.build().toString());
         builder.clear();
         assertEquals("[]", builder.build().toString());
+        builder.toChain();
         Map<String, Object> value = U.objectBuilder()
             .add("firstName", "John")
             .add("lastName", "Smith")