Added UI for plugin system and upnp example

- Added wip UI for plugin tag system
- Added upnp port forwarder plugin
- Added error and fatal printout for plugins
- Optimized UI flow for plugin context window
- Added dev web server for plugin development purpose

src/web/components/plugincontext.html

@@ -45,6 +45,9 @@
     function resizeIframe() {
         let iframe = document.getElementById('pluginContextLoader');
         let mainMenuHeight = document.getElementById('mainmenu').offsetHeight;
+        if (mainMenuHeight == 0){
+            mainMenuHeight = window.innerHeight - 198; //Fallback to window height
+        }
         iframe.style.height = mainMenuHeight + 'px';
     }
 
@@ -57,6 +60,4 @@
         //On switch over to this page, load info
         resizeIframe();
     }
-
-    initPluginUIView();
 </script>