Query regarding logic

[jeremyquinton]

This is a great little library found it really useful. I was just reading the source and Im new to go I had a thought around these lines thought maybe worth mentioning.

https://github.com/jhoonb/archivex/blob/master/archivex.go#L53-L60

	if strings.HasSuffix(name, ".zip") != true {
		if strings.HasSuffix(name, ".tar.gz") == true {
			name = strings.Replace(name, ".tar.gz", ".zip", -1)
		} else {
			name = name + ".zip"
		}
	}
	z.Name = name

could it not be better written as

	if strings.HasSuffix(name, ".zip") == true {
		z.Name = name
	}

	if strings.HasSuffix(name, ".tar.gz") == true {
		z.Name = strings.Replace(name, ".tar.gz", ".zip", -1)
	}

	if z.Name == "" {
		z.Name = name + ".zip"
	}

the idea being that code with one level of indentation is easier to read. If you think that is an improvement Id be happy to do a PR else you can close my issue. Thanks again for the library works really well.