Add support for disabling plugins (#4141)

* Move timestamp to own file
* Backend changes
* UI changes

internal/api/server.go

@@ -295,6 +295,10 @@ func cssHandler(c *config.Instance, pluginCache *plugin.Cache) func(w http.Respo
 		var paths []string
 
 		for _, p := range pluginCache.ListPlugins() {
+			if !p.Enabled {
+				continue
+			}
+
 			paths = append(paths, p.UI.CSS...)
 		}
 
@@ -318,6 +322,10 @@ func javascriptHandler(c *config.Instance, pluginCache *plugin.Cache) func(w htt
 		var paths []string
 
 		for _, p := range pluginCache.ListPlugins() {
+			if !p.Enabled {
+				continue
+			}
+
 			paths = append(paths, p.UI.Javascript...)
 		}