Make logs reopen if thier files are deletd or moved.

common/messages/messageTrace.go

@@ -74,6 +74,14 @@ func getTraceFile(name string) (f *os.File) {
 		files = make(map[string]*os.File)
 	}
 	f, _ = files[name]
+	if f != nil {
+		_, err := os.Stat(name)
+		if os.IsNotExist(err) {
+			// The file was deleted out from under us
+			f.Close() // close the old log
+		}
+		f = nil // make the code reopen the file
+	}
 	if f == nil {
 		fmt.Println("Creating " + name)
 		var err error