Vendor all dependencies

Uses godep to vendor dependencies. Godeps is not necessary during build,
golang's new vendor support is used instead.

vendor/github.com/godbus/dbus/homedir.go

@@ -0,0 +1,28 @@
+package dbus
+
+import (
+	"os"
+	"sync"
+)
+
+var (
+	homeDir     string
+	homeDirLock sync.Mutex
+)
+
+func getHomeDir() string {
+	homeDirLock.Lock()
+	defer homeDirLock.Unlock()
+
+	if homeDir != "" {
+		return homeDir
+	}
+
+	homeDir = os.Getenv("HOME")
+	if homeDir != "" {
+		return homeDir
+	}
+
+	homeDir = lookupHomeDir()
+	return homeDir
+}