making sure message keys with upgrade status of deleted are not exported to xml files, important fix: write xml files in utf-8 if the specified charset is not supported by tcl, correcting some log statements
adding message catalog upgrade support to the acs-lang package. message keys and messages now have an upgrade status (added, deleted, updated). Being more rigorous about determining what is a catalog file and moving this logic to the acs-bootstrap-installer package (apm_is_catalog_file) as it is needed before the acs-lang library is loaded. Updated procedure documentation.