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/generate.go

@@ -0,0 +1,76 @@
+// 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 (
+	"io"
+	"text/template"
+)
+
+// binAsset holds information about a single asset to be processed.
+type binAsset struct {
+	File
+
+	opts        *GenerateOptions
+	Hash        []byte // Generated hash of file.
+	mangledName string
+}
+
+// Generate writes the generated Go code to w.
+func (f Files) Generate(w io.Writer, opts *GenerateOptions) error {
+	if opts == nil {
+		opts = &GenerateOptions{Package: "main"}
+	}
+
+	err := opts.validate()
+	if err != nil {
+		return err
+	}
+
+	assets := make([]binAsset, 0, len(f))
+	for i, file := range f {
+		asset := binAsset{
+			File: file,
+
+			opts: opts,
+		}
+
+		if opts.Hash != nil {
+			if i != 0 {
+				opts.Hash.Reset()
+			}
+
+			if err = asset.copy(opts.Hash); err != nil {
+				return err
+			}
+
+			asset.Hash = opts.Hash.Sum(nil)
+		}
+
+		assets = append(assets, asset)
+	}
+
+	return baseTemplate.Execute(w, struct {
+		*GenerateOptions
+		Assets []binAsset
+	}{opts, assets})
+}
+
+var baseTemplate = template.Must(template.New("base").Parse(`
+{{- template "header" .}}
+
+{{if or $.Debug $.Dev -}}
+{{- template "debug" . -}}
+{{- else -}}
+{{- template "release" . -}}
+{{- end}}
+
+{{template "common" . -}}
+
+{{- if $.AssetDir}}
+
+{{template "tree" . -}}
+{{- end}}
+`))