Improve checkOS method for better handling existing browser

[Bunchhieng]

Current code

func checkOS() string {
	chrome := ""
	if runtime.GOOS == "windows" {
		chrome = "chrome"
	} else if runtime.GOOS == "darwin" {
		chrome = "Google Chrome"
	}
	return chrome
}

[kels-c]

Suggestion/slightly outside of this issue: Instead of having the user specify a browser, what about executing a system command to open their default browser?

[Bunchhieng]

@kolten please checkout #1 and #2

[zpeters]

We might be able to simplify browser selection. Let me know what you think.

#1 if the user specifies --browser explicitly use that exact path/command
#2 if no #1, then find the users default browser. For Macos i believe you can use "open http://myurl" and it will launch with the default browser. For windows and linux there is probably something similar

This could potentially simplify your code in the future.

What do you think?

[sarlalian]

For windows I believe it is "start http://myurl" and for linux it is "xdg-open http://myurl"