Move to yaml-based configuration

This commit updates the configuration to be yaml-based and updates the
configuration to read in a yaml file.

internal/dis/component/server/home/home.go

@@ -51,7 +51,7 @@ func (home *Home) HandleRoute(ctx context.Context, route string) (http.Handler,
 	dflt.Fallback = home.publicHandler(ctx)
 
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		slug, ok := home.Config.SlugFromHost(r.Host)
+		slug, ok := home.Config.HTTP.SlugFromHost(r.Host)
 		switch {
 		case !ok:
 			http.NotFound(w, r)

internal/dis/component/server/home/public.go

@@ -68,7 +68,7 @@ func (home *Home) publicHandler(ctx context.Context) http.Handler {
 		// prepare about
 		pc.aboutContext.Logo = logoHTML
 		pc.aboutContext.Instances = home.homeInstances.Get(nil)
-		pc.aboutContext.SelfRedirect = home.Config.SelfRedirect.String()
+		pc.aboutContext.SelfRedirect = home.Config.Theme.SelfRedirect.String()
 
 		// render the about template
 

internal/dis/component/server/home/redirect.go

@@ -18,7 +18,7 @@ func (home *Home) loadRedirect(ctx context.Context) (redirect Redirect, err erro
 	redirect.Permanent = false
 
 	// load the overrides file
-	overrides, err := home.Environment.Open(home.Config.SelfOverridesFile)
+	overrides, err := home.Environment.Open(home.Config.Paths.OverridesJSON)
 	if err != nil {
 		return redirect, err
 	}