fix pre/post increment operator precedence

Decremented pre/post increment operator precedence to fix printing this code:

    public class Cls {
      public m1() {
        int count;
        m.a(new F() {
          public void T(E e) {
            count++;
          }
        });
      }
    }

`count++;` part was being printed as `(count++);` which is not valid syntax.

Please note that this changes are not extensively tested. It worked fine in my case so I'm sending a pull request(either way there is a bug in printing post/pre increment operators).