Allow trailing array commas (https://github.com/HaxeFoundation/hscript/pull/139)

TestHScript.hx

@@ -57,6 +57,7 @@ class TestHScript extends TestCase {
 		assertScript("3 * 2 // + 5 \n + 6",12);
 		assertScript("3 /* 2\n */ + 5",8);
 		assertScript("[55,66,77][1]",66);
+		assertScript("[11,22,33,][2]", 33);
 		assertScript("var a = [55]; a[0] *= 2; a[0]",110);
 		assertScript("x",55,{ x : 55 });
 		assertScript("var y = 33; y",33);

hscript/Parser.hx

@@ -486,8 +486,11 @@ class Parser {
 				if(!first) {
 					if(tk != TComma)
 						unexpected(tk);
-					else 
+					else {
 						tk = token();
+						if (tk == TBkClose)
+							break;
+					}
 				}
 				first = false;
 				push(tk);