disassemble: fix opcode range check

src/assembler.rs

@@ -39,7 +39,7 @@ pub fn disassemble(bytecode: &Vec< AssemblyWord >) -> Vec< String > {
             }
             AssemblyWord::Lit(w) => {
                 if remaining_params == 0 {
-                    if *w < 18 {
+                    if *w < 32 {
                         let inst : VM_Instruction = unsafe { std::mem::transmute(*w) };
                         result.push(format!("{:?}", inst));
                         remaining_params = inst.param_length();