Move wisski instance code to separate package

internal/component/instances/wisski_props.go

@@ -1,29 +0,0 @@
-package instances
-
-import (
-	"fmt"
-	"net/url"
-)
-
-// Domain returns the full domain name of this WissKI
-func (wisski WissKI) Domain() string {
-	return fmt.Sprintf("%s.%s", wisski.Slug, wisski.instances.Config.DefaultDomain)
-}
-
-// URL returns the public URL of this instance
-func (wisski WissKI) URL() *url.URL {
-	// setup domain and path
-	url := &url.URL{
-		Host: wisski.Domain(),
-		Path: "/",
-	}
-
-	// use http or https scheme depending on if the distillery has it enabled
-	if wisski.instances.Config.HTTPSEnabled() {
-		url.Scheme = "https"
-	} else {
-		url.Scheme = "http"
-	}
-
-	return url
-}