deploytool: Add README.md, migrate docs to it.

deploytool/cmd/config.go

Index: deploytool/cmd/config.go
diff --git a/deploytool/cmd/config.go b/deploytool/cmd/config.go
deleted file mode 100644
index 63f00becc63942d3774ace7eb0507f319d385f33..0000000000000000000000000000000000000000
--- a/deploytool/cmd/config.go
+++ /dev/null
@@ -1,40 +0,0 @@
-// Copyright 2016 The LUCI Authors. All rights reserved.
-// Use of this source code is governed under the Apache License, Version 2.0
-// that can be found in the LICENSE file.
-
-package main
-
-import (
-	"path/filepath"
-
-	"github.com/luci/luci-go/common/errors"
-	log "github.com/luci/luci-go/common/logging"
-	"github.com/luci/luci-go/deploytool/api/deploy"
-
-	"github.com/mitchellh/go-homedir"
-	"golang.org/x/net/context"
-)
-
-const userCfgName = ".luci_deploytool"
-
-func loadUserConfig(c context.Context, cfg *deploy.UserConfig) error {
-	path, err := homedir.Dir()
-	if err != nil {
-		log.WithError(err).Warningf(c, "Failed to get user home directory; cannot load local config.")
-		return nil
-	}
-
-	configPath := filepath.Join(path, userCfgName)
-	switch err := unmarshalTextProtobuf(configPath, cfg); {
-	case err == nil:
-		log.Infof(c, "Loaded user config from: %s", configPath)
-
-	case isNotExist(err):
-		log.Debugf(c, "No user config found at: %s", configPath)
-
-	default:
-		return errors.Annotate(err).Reason("failed to load config at [%(path)s]").D("path", configPath).Err()
-	}
-
-	return nil
-}