use <style>  instead of <link> to hide WS
add excluded pages option
modified option page's style
add domain-match-exclude, excluded mail.live.com by default
fixed defaultOptions in option.js
delete comment in <style>
add isHidden/redraw func for webkit-scrollbar
improved accuracy of redrawWebkitScrollbar()
fixed no refresh at document_start
fixed unredraw bug if is iframed
fixed to adjust rail size in zoom
add minimum bar size option
remove rail-config from options
fix scrollbar positions
remove rail's border on hover
set border instead of box-shadow
modified style.less
revert styles: thumbs' box-shadow, rails' border
change webkitScrollbar style
update version in manifest.json