Switch to new vendor directory layout

Fixes #113

Signed-off-by: Marcos Lilljedahl <marcosnils@gmail.com>

vendor/github.com/opencontainers/runc/libcontainer/stacktrace/capture_test.go

@@ -0,0 +1,31 @@
+package stacktrace
+
+import (
+	"strings"
+	"testing"
+)
+
+func captureFunc() Stacktrace {
+	return Capture(0)
+}
+
+func TestCaptureTestFunc(t *testing.T) {
+	stack := captureFunc()
+
+	if len(stack.Frames) == 0 {
+		t.Fatal("expected stack frames to be returned")
+	}
+
+	// the first frame is the caller
+	frame := stack.Frames[0]
+	if expected := "captureFunc"; frame.Function != expected {
+		t.Fatalf("expteced function %q but recevied %q", expected, frame.Function)
+	}
+	expected := "github.com/opencontainers/runc/libcontainer/stacktrace"
+	if !strings.HasSuffix(frame.Package, expected) {
+		t.Fatalf("expected package %q but received %q", expected, frame.Package)
+	}
+	if expected := "capture_test.go"; frame.File != expected {
+		t.Fatalf("expected file %q but received %q", expected, frame.File)
+	}
+}