diff --git a/vendor/cmd/go/internal/web2/web.go b/vendor/cmd/go/internal/web2/web.go
new file mode 100644
index 0000000..0a7b8de
--- /dev/null
+++ b/vendor/cmd/go/internal/web2/web.go
@@ -0,0 +1,255 @@
+// 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.
+
+package web2
+
+import (
+	"bytes"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"path/filepath"
+	"runtime/debug"
+	"strings"
+	"sync"
+)
+
+var TraceGET = false
+var webstack = false
+
+func init() {
+	flag.BoolVar(&TraceGET, "webtrace", TraceGET, "trace GET requests")
+	flag.BoolVar(&webstack, "webstack", webstack, "print stack for GET requests")
+}
+
+type netrcLine struct {
+	machine  string
+	login    string
+	password string
+}
+
+var netrcOnce sync.Once
+var netrc []netrcLine
+
+func parseNetrc(data string) []netrcLine {
+	var nrc []netrcLine
+	var l netrcLine
+	for _, line := range strings.Split(string(data), "\n") {
+		f := strings.Fields(line)
+		for i := 0; i < len(f)-1; i += 2 {
+			switch f[i] {
+			case "machine":
+				l.machine = f[i+1]
+			case "login":
+				l.login = f[i+1]
+			case "password":
+				l.password = f[i+1]
+			}
+		}
+		if l.machine != "" && l.login != "" && l.password != "" {
+			nrc = append(nrc, l)
+			l = netrcLine{}
+		}
+	}
+	return nrc
+}
+
+func readNetrc() {
+	data, err := ioutil.ReadFile(filepath.Join(os.Getenv("HOME"), ".netrc"))
+	if err != nil {
+		return
+	}
+	netrc = parseNetrc(string(data))
+}
+
+type getState struct {
+	req      *http.Request
+	resp     *http.Response
+	body     io.ReadCloser
+	non200ok bool
+}
+
+type Option interface {
+	option(*getState) error
+}
+
+func Non200OK() Option {
+	return optionFunc(func(g *getState) error {
+		g.non200ok = true
+		return nil
+	})
+}
+
+type optionFunc func(*getState) error
+
+func (f optionFunc) option(g *getState) error {
+	return f(g)
+}
+
+func DecodeJSON(dst interface{}) Option {
+	return optionFunc(func(g *getState) error {
+		if g.resp != nil {
+			return json.NewDecoder(g.body).Decode(dst)
+		}
+		return nil
+	})
+}
+
+func ReadAllBody(body *[]byte) Option {
+	return optionFunc(func(g *getState) error {
+		if g.resp != nil {
+			var err error
+			*body, err = ioutil.ReadAll(g.body)
+			return err
+		}
+		return nil
+	})
+}
+
+func Body(body *io.ReadCloser) Option {
+	return optionFunc(func(g *getState) error {
+		if g.resp != nil {
+			*body = g.body
+			g.body = nil
+		}
+		return nil
+	})
+}
+
+func Header(hdr *http.Header) Option {
+	return optionFunc(func(g *getState) error {
+		if g.resp != nil {
+			*hdr = CopyHeader(g.resp.Header)
+		}
+		return nil
+	})
+}
+
+func CopyHeader(hdr http.Header) http.Header {
+	if hdr == nil {
+		return nil
+	}
+	h2 := make(http.Header)
+	for k, v := range hdr {
+		v2 := make([]string, len(v))
+		copy(v2, v)
+		h2[k] = v2
+	}
+	return h2
+}
+
+var cache struct {
+	mu    sync.Mutex
+	byURL map[string]*cacheEntry
+}
+
+type cacheEntry struct {
+	mu   sync.Mutex
+	resp *http.Response
+	body []byte
+}
+
+var httpDo = http.DefaultClient.Do
+
+func SetHTTPDoForTesting(do func(*http.Request) (*http.Response, error)) {
+	if do == nil {
+		do = http.DefaultClient.Do
+	}
+	httpDo = do
+}
+
+func Get(url string, options ...Option) error {
+	if TraceGET || webstack {
+		println("GET", url)
+		if webstack {
+			println(string(debug.Stack()))
+		}
+	}
+
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return err
+	}
+
+	netrcOnce.Do(readNetrc)
+	for _, l := range netrc {
+		if l.machine == req.URL.Host {
+			req.SetBasicAuth(l.login, l.password)
+			break
+		}
+	}
+
+	g := &getState{req: req}
+	for _, o := range options {
+		if err := o.option(g); err != nil {
+			return err
+		}
+	}
+
+	cache.mu.Lock()
+	e := cache.byURL[url]
+	if e == nil {
+		e = new(cacheEntry)
+		if !strings.HasPrefix(url, "file:") {
+			if cache.byURL == nil {
+				cache.byURL = make(map[string]*cacheEntry)
+			}
+			cache.byURL[url] = e
+		}
+	}
+	cache.mu.Unlock()
+
+	e.mu.Lock()
+	if strings.HasPrefix(url, "file:") {
+		body, err := ioutil.ReadFile(req.URL.Path)
+		if err != nil {
+			e.mu.Unlock()
+			return err
+		}
+		e.body = body
+		e.resp = &http.Response{
+			StatusCode: 200,
+		}
+	} else if e.resp == nil {
+		resp, err := httpDo(req)
+		if err != nil {
+			e.mu.Unlock()
+			return err
+		}
+		e.resp = resp
+		// TODO: Spool to temp file.
+		body, err := ioutil.ReadAll(resp.Body)
+		resp.Body.Close()
+		resp.Body = nil
+		if err != nil {
+			e.mu.Unlock()
+			return err
+		}
+		e.body = body
+	}
+	g.resp = e.resp
+	g.body = ioutil.NopCloser(bytes.NewReader(e.body))
+	e.mu.Unlock()
+
+	defer func() {
+		if g.body != nil {
+			g.body.Close()
+		}
+	}()
+
+	if !g.non200ok && g.resp.StatusCode != 200 {
+		return fmt.Errorf("unexpected status (%s): %v", url, g.resp.Status)
+	}
+
+	for _, o := range options {
+		if err := o.option(g); err != nil {
+			return err
+		}
+	}
+	return err
+}
diff --git a/vendor/cmd/go/internal/web2/web_test.go b/vendor/cmd/go/internal/web2/web_test.go
new file mode 100644
index 0000000..c6f6b1e
--- /dev/null
+++ b/vendor/cmd/go/internal/web2/web_test.go
@@ -0,0 +1,35 @@
+// 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.
+
+package web2
+
+import (
+	"reflect"
+	"testing"
+)
+
+var testNetrc = `
+machine api.github.com
+  login user
+  password pwd
+
+machine incomlete.host
+  login justlogin
+  
+machine test.host
+login user2
+password pwd2
+`
+
+func TestReadNetrc(t *testing.T) {
+	lines := parseNetrc(testNetrc)
+	want := []netrcLine{
+		{"api.github.com", "user", "pwd"},
+		{"test.host", "user2", "pwd2"},
+	}
+
+	if !reflect.DeepEqual(lines, want) {
+		t.Errorf("parseNetrc:\nhave %q\nwant %q", lines, want)
+	}
+}