_setMenuitemAttributes
"unread" attribute cleanup
"selected" attribute cleanup
Merge branch 'cleanup' into develop

Conflicts:
	chrome/content/tabutils-st.js
	chrome/content/tabutils.js
	chrome/locale/de/tabutils.dtd
	chrome/locale/es-ES/tabutils.dtd
	chrome/locale/it/tabutils.dtd
	chrome/locale/ja-JP/tabutils.dtd
	chrome/locale/pl/tabutils.dtd
	chrome/locale/pt-BR/tabutils.dtd
	chrome/locale/ru/tabutils.dtd
	chrome/locale/zh-TW/tabutils.dtd