Fix bug ZK-1693: Dial chart customize color issues
http://tracker.zkoss.org/browse/ZK-1693
Fix bug ZK-1692: widget.isVisible API doesn't work properly
http://tracker.zkoss.org/browse/ZK-1692
Merge remote-tracking branch 'VincentJian/B65-ZK-1692'
Fix IE8 issue
Re-fix bug ZK-1692
Merge branch 'master' of github.com:zkoss/zk into flex
Merge remote-tracking branch 'Neillee/master'
fix IE 6 issue
Merge remote-tracking branch 'VincentJian/flex'
fix zk-1698 mvvm tree performance
fix ZK-1691: Dropupload has "native" property (reserved identifier in EL)
fine tune exception handling