.state files do not respect --working flag

[m-a-martin]

If you run beast on an xml in a subdirectory of the currently directory with the --working flag (ex: beast --working beast_xml/test_run/test.xml) all output files except the .state files will correctly end up in the subdirectory (here beast_xml/test_run). Expected behavior is for the .state files to also be saved in the subdirectory.