Fix the invalid '\x' escape when QQ is too long

When `int(QQ)` is greater than the `sys.maxint`, the `hex(int(QQ))` will have an extra character 'L', which will make `PSWEncrypt.PSWEncrypt.hexchar2bin` crash. So I change the code in the `PSWEncrypt.PSWEncrypt.BinUser` to remove the extra 'L' if necessary.

Now, the program can deal with a long QQ account (but still must consist of pure digits).