WICKET-5241 RequestLogger's server duration does not include 'detach duration'

Track the request logger's end time after all pages have been detached.
This way it shows the correct time fo the page rendering.

(cherry picked from commit 1d9ef1107958deb83f9f87a9e8be80d48b267ecf)
WICKET-5241 RequestLogger's server duration does not include 'detach duration'

Remove detaching of the pages in RequestAdapter#commitRequest().

The page has been detached few calls ago:
In org.apache.wicket.request.cycle.RequestCycle#onDetach:

try
{
  requestHandlerExecutor.detach();   // detaches pages #1
}
finally
{
  listeners.onDetach(this);          // detaches pages #2 (no more)
}

(cherry picked from commit 48eaae68fe0327b421cb2ffb56912cd180bf6728)
WICKET-5340 CssAttributeModifier and StyleAttributeModifier

(cherry picked from commit 526280230eb1ae69ec9dfbf801557c2bbc7b07e1)
WICKET-5340 CssAttributeModifier and StyleAttributeModifier

(cherry picked from commit a20cdb51cc77765fff0a82d66f02e4abc68c31b8)
WICKET-5340 CssAttributeModifier and StyleAttributeModifier
WICKET-5628 Introduce a marker interface for exception which are recommended to be handler by the framework