Bug fixed, B65-ZK-1588: bandbox popup should drop up when the space
between the bandbox and the bottom of browser is not enough
http://tracker.zkoss.org/browse/ZK-1588
1. Fixed  the bug ZK-1862: Should not echo parameter value back to client
2. update the Javadoc of the maxlength property from InputElement.java
minor fix
Merge branch 'master' of github.com:zkoss/zk