fix: Add extra newline after printing enum values

[sanderploegsma]

This partly solves #4129 by adding an extra newline after printing the enum values.

So instead of printing this:

public enum SimpleEnum {

    CONSTANT;}

It now prints this:

public enum SimpleEnum {

    CONSTANT;
}

This does have a small impact on enums with members, as previously they would be printed like this:

public enum EnumWithMembers {

    ONE,
    TWO,
    THREE;
    private static int len = -1;

    public static void f() {
        len = 44;
    }
}

And now they will be printed like this:

public enum EnumWithMembers {

    ONE,
    TWO,
    THREE;

    private static int len = -1;

    public static void f() {
        len = 44;
    }
}

To be honest I prefer the second anyway.

[SirYwell]

Looks good! Thanks.