ignore idea project files
Merge remote-tracking branch 'upstream/master' into trunk
Merge remote-tracking branch 'upstream/master' into trunk
git ignore
Merge remote-tracking branch 'upstream/master' into trunk
Merge remote-tracking branch 'upstream/master' into trunk
Merge remote-tracking branch 'upstream/master' into trunk
Merge remote-tracking branch 'upstream/master' into trunk
Merge branch 'trunk', remote-tracking branch 'upstream/master' into trunk
Merge remote-tracking branch 'upstream/master' into trunk
Merge remote-tracking branch 'upstream/master' into trunk
Merge branch 'trunk', remote-tracking branch 'upstream/master' into trunk
Merge remote-tracking branch 'upstream/master' into trunk
WICKET-4998 + WICKET-4990 removed all inline event handling, use
stopImmediatePropagation() to prevent other behaviors from firing
next development version
improved javadoc
WICKET-4444 Add a callback to the Session which is called when the HttpSession is invalidated
WICKET-4444 Add a callback to the Session which is called when the HttpSession is invalidated

Add a deprecated constructor that forwards to the new one.
Fixes Clirr error report
WICKET-5003 Add wicket:for attribute in wicket.xsd
WICKET-5006 Improve null display value in AbstractSingleSelectChoice