2012-08-07  Andreas J. Guelzow <aguelzow@pyrshep.ca>

	* src/gui-file.c: adjust all calls to workbook_update_history
	(gui_file_save_as): get the correct file name,
	* src/main-application.c: adjust all calls to workbook_update_history
	* src/workbook-priv.h (_Workbook): add fields
	* src/workbook-view.c (wb_view_save_as): save all file names
	* src/workbook.c (workbook_update_history): add argument and change all callers
	(workbook_dispose): free saved export file name
	(workbook_set_saveinfo): save format level for exports too
	(workbook_get_last_export_uri): new
	* src/workbook.h (workbook_update_history): add argument
	(workbook_get_last_export_uri): new