Implement Go language binding (#1196)

Implement Go binding APIs of runtime, module and instance
Add sample, build scripts and update the document

Co-authored-by: venus-taibai <97893654+venus-taibai@users.noreply.github.com>

language-bindings/go/wamr/instance_test.go

@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2019 Intel Corporation.  All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+ */
+
+package wamr
+
+import (
+    //"github.com/stretchr/testify/assert"
+    "testing"
+)
+
+func TestInstance(t *testing.T) {
+    /* TODO */
+}
+
+func TestCallFunc(t *testing.T) {
+    /* TODO */
+}