fix ZK-1640 CommandSend2WrongViewModel
Merge commit 'zk-1640' into zkoss-master
Feature ZK-1638: Preload_Image attribute support configuration in zk.xml as a library property
http://tracker.zkoss.org/browse/ZK-1638
Fix bug ZK-1658: chosenbox disappears after user select a value
http://tracker.zkoss.org/browse/ZK-1658
Merge remote-tracking branch 'VincentJian/B60-ZK-1658'
Fix bug ZK-1662: Overlapped window z-index inconsistent behavior
http://tracker.zkoss.org/browse/ZK-1662
re-fix ZK-878, wrong value validation should be done before user's validator
Fix bug ZK-1661: Popup list of chosenbox do not scroll when navigate with keyboard
http://tracker.zkoss.org/browse/ZK-1661
fix zk-1666 binding toolbarbutton
Fix bug ZK-1660: Chosenbox with ListModel issue
http://tracker.zkoss.org/browse/ZK-1660
Merge branch '6.0'
Fix bug ZK-1664: Chosenbox input value may discard while typing
http://tracker.zkoss.org/browse/ZK-1664