Move to vendor

Signed-off-by: Olivier Gambier <olivier@docker.com>

vendor/github.com/bugsnag/osext/osext_procfs.go

@@ -0,0 +1,25 @@
+// Copyright 2012 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.
+
+// +build linux netbsd openbsd
+
+package osext
+
+import (
+	"errors"
+	"os"
+	"runtime"
+)
+
+func executable() (string, error) {
+	switch runtime.GOOS {
+	case "linux":
+		return os.Readlink("/proc/self/exe")
+	case "netbsd":
+		return os.Readlink("/proc/curproc/exe")
+	case "openbsd":
+		return os.Readlink("/proc/curproc/file")
+	}
+	return "", errors.New("ExecPath not implemented for " + runtime.GOOS)
+}