willmadison: add hello world demo program for Gophercon contributors workshop

Change-Id: I4cd2bf1b14ccc7f6c338e7b09799f05afdd1d153
Reviewed-on: https://go-review.googlesource.com/132262
Reviewed-by: Kevin Burke <kev@inburke.com>
Run-TryBot: Kevin Burke <kev@inburke.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

willmadison/main.go

@@ -0,0 +1,12 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This package is a playground for contribution best practices
+package main
+
+import "fmt"
+
+func main() {
+	fmt.Println("Hello, Welcome to scratch Will!")
+}