Implement new[size] operator for arrays

Example syntax:
```js
temp.a = new[3];
temp.a[1] = 2;
//Output 0,2,0
echo(a);
```

Opcode value (from decompiler):
```
OPCODE(NewArray, 0x26)
```

The `NewArray` opcode basically has a size parameter that indicates how big the array should be. It will pop the top value from the stack as the size.