cleanup and renaming of import/export procs in lang::catalog namespace. Now there are really only two public procs to know about: lang::catalog::import and lang::catalog::export. Updating all invocations of the procs and test cases. Adding proc lang::message::unregister for deleting message keys - used in test case teardown.
Because of problem exporting digits in arabic locale (AR_LB with ISO-8859-6) we have now changed to export all catalog files in utf-8 except when ISO-8859-1 can be used. Easiest would be to export all catalog files in utf-8, however, out of fear of hand editing of catalog files messing with the utf-8 encoding we don't. Adding encoding attribute to xml tag of message catalog files. Removing redundant file name prefixing of log statements.