Fixed #272: Catching more appengine package locations

tree/tree.go

diff --git a/tree/tree.go b/tree/tree.go
index 96c7d3e..1be49a5 100644
--- a/tree/tree.go
+++ b/tree/tree.go
@@ -146,7 +146,9 @@
 	// If this is "C", we're dealing with cgo
 	if name == "C" {
 		info.Loc = dependency.LocCgo
-	} else if name == "appengine" || strings.HasPrefix(name, "appengine/") {
+	} else if name == "appengine" || name == "appengine_internal" ||
+		strings.HasPrefix(name, "appengine/") ||
+		strings.HasPrefix(name, "appengine_internal/") {
 		// Appengine is a special case when it comes to Go builds. It is a local
 		// looking package only available within appengine. It's a special case
 		// where Google products are playing with each other.