Add basic json and html file types

Added basic json and html file support that should be included as
project files.

Note: Those are the basic HTML5 project source file types that are
missing.

Plugins/Editor/VSCode.cs

@@ -33,7 +33,7 @@ public static class VSCode
         /// <summary>
         /// Additional File Extensions
         /// </summary>
-        public const string FileExtensions = ".ts, .bjs, .javascript";
+        public const string FileExtensions = ".ts, .bjs, .javascript, .json, .html";
 
         /// <summary>
         /// Download URL for Unity Debbuger