support blockquote tag.
added an option to prefer HTML part in multipart/alternative.
refactored MessageView/MimeView/
src/printing.c: modified debug output.
src/textview.c: insert space between continuous links to avoid non-responsive links.
updated NEWS.
filesel: automatically modify file extension when file type is changed.
filesel: save selected file type.
updated ja.po.
updated Japanese manual.
raise compose window when the external editor exits.
updated NEWS.
updated po.
stabilize the order of templates.
src/template.c: template_compare_id(): fixed constness.
updated config.guess and config.sub.