Add webgl2 IDL spec and generated code (#18)

I've added WebGL 2 example code to `DOMKitDemo` ported from https://webgl2fundamentals.org/webgl/lessons/webgl-fundamentals.html, which is under MIT/BSD3-like license (added inline to the file), looks like this in action after you press the button. Just a pink triangle, but it finally works!

Author: MaxDesiatov

Package.swift

@@ -8,35 +8,43 @@ let package = Package(
     products: [
         .executable(
             name: "DOMKitDemo",
-            targets: ["DOMKitDemo"]),
+            targets: ["DOMKitDemo"]
+        ),
         .library(
             name: "DOMKit",
-            targets: ["DOMKit"]),
+            targets: ["DOMKit"]
+        ),
         .library(name: "WebIDL", targets: ["WebIDL"]),
         .executable(name: "WebIDLToSwift", targets: ["WebIDLToSwift"]),
     ],
     dependencies: [
         .package(
             url: "https://github.com/swiftwasm/JavaScriptKit.git",
-            .branch("main")),
+            .revision("95d0c4cd78b48ffc7e19c618d57c3244917be09a")
+        ),
     ],
     targets: [
         .target(
             name: "DOMKitDemo",
-            dependencies: ["DOMKit"]),
+            dependencies: ["DOMKit"]
+        ),
         .target(
             name: "DOMKit",
-            dependencies: ["ECMAScript", "JavaScriptKit", .product(name: "JavaScriptEventLoop", package: "JavaScriptKit")]),
+            dependencies: ["ECMAScript", "JavaScriptKit", .product(name: "JavaScriptEventLoop", package: "JavaScriptKit")]
+        ),
         // This support library should be moved to JavaScriptKit
         .target(name: "ECMAScript", dependencies: [
             "JavaScriptKit",
-            .product(name: "JavaScriptEventLoop", package: "JavaScriptKit")]),
+            .product(name: "JavaScriptEventLoop", package: "JavaScriptKit"),
+        ]),
         .target(name: "WebIDL"),
         .target(
             name: "WebIDLToSwift",
-            dependencies: ["WebIDL"]),
+            dependencies: ["WebIDL"]
+        ),
         .testTarget(
             name: "DOMKitTests",
-            dependencies: ["DOMKit"]),
+            dependencies: ["DOMKit"]
+        ),
     ]
 )