[feature] Filter empty class output

[ohyeah521]

Describe your idea

It is recommended to add a parameter to the command line and not output empty classes.Obfuscation software will insert junk empty classes into the original dex file. It is recommended to add a command line parameter to filter the output of such empty classes to improve program execution efficiency and reduce disk usage.For example, the following garbage code：

package Wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww;

public final class Wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww {
}