chore(build): use third_party.go

use the third_party.go project to replace our update script. This
requires moving a few things around and gets rid of a few annoying bugs:

- You can now bump individual packages
- A new src directory isn't created on build
- Less shell scripting!
- Things get built into ./bin/

third_party/github.com/gorilla/context/context_test.go

@@ -1,66 +0,0 @@
-// Copyright 2012 The Gorilla 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 context
-
-import (
-	"net/http"
-	"testing"
-)
-
-type keyType int
-
-const (
-	key1 keyType = iota
-	key2
-)
-
-func TestContext(t *testing.T) {
-	assertEqual := func(val interface{}, exp interface{}) {
-		if val != exp {
-			t.Errorf("Expected %v, got %v.", exp, val)
-		}
-	}
-
-	r, _ := http.NewRequest("GET", "http://localhost:8080/", nil)
-
-	// Get()
-	assertEqual(Get(r, key1), nil)
-
-	// Set()
-	Set(r, key1, "1")
-	assertEqual(Get(r, key1), "1")
-	assertEqual(len(data[r]), 1)
-
-	Set(r, key2, "2")
-	assertEqual(Get(r, key2), "2")
-	assertEqual(len(data[r]), 2)
-
-	//GetOk
-	value, ok := GetOk(r, key1)
-	assertEqual(value, "1")
-	assertEqual(ok, true)
-
-	value, ok = GetOk(r, "not exists")
-	assertEqual(value, nil)
-	assertEqual(ok, false)
-
-	Set(r, "nil value", nil)
-	value, ok = GetOk(r, "nil value")
-	assertEqual(value, nil)
-	assertEqual(ok, true)
-
-	// Delete()
-	Delete(r, key1)
-	assertEqual(Get(r, key1), nil)
-	assertEqual(len(data[r]), 2)
-
-	Delete(r, key2)
-	assertEqual(Get(r, key2), nil)
-	assertEqual(len(data[r]), 1)
-
-	// Clear()
-	Clear(r)
-	assertEqual(len(data), 0)
-}