Refactor repository layout and convert build system to Mage.

This commit implements a massive refactor of the repository, and
moves the build system over to use Mage (magefile.org) which should
allow seamless building across multiple platforms.

tools/vendor/github.com/tmthrgd/go-bindata/buffers.go

@@ -0,0 +1,49 @@
+// Copyright 2017 Tom Thorogood. All rights reserved.
+// Use of this source code is governed by a Modified
+// BSD License that can be found in the LICENSE file.
+
+package bindata
+
+import (
+	"bytes"
+	"io"
+	"os"
+	"sync"
+)
+
+var bufPool = &sync.Pool{
+	New: func() interface{} {
+		return new(bytes.Buffer)
+	},
+}
+
+func (asset *binAsset) copy(w io.Writer) error {
+	rc, err := asset.Open()
+	if err != nil {
+		return err
+	}
+
+	n := 4 * 1024
+	if s, ok := rc.(interface {
+		Stat() (os.FileInfo, error)
+	}); ok {
+		if fi, err := s.Stat(); err == nil {
+			// Don't preallocate a huge buffer, just in case.
+			if size := fi.Size(); size < 1e9 {
+				n = int(size) + bytes.MinRead
+			}
+		}
+	}
+
+	buf := bufPool.Get().(*bytes.Buffer)
+	buf.Grow(n)
+
+	_, err = io.CopyBuffer(w, rc, buf.Bytes()[:buf.Cap()])
+
+	if closeErr := rc.Close(); err == nil {
+		err = closeErr
+	}
+
+	bufPool.Put(buf)
+	return err
+}