add locale variable
add support for localized / message regions in templates
unsuccessfull attempt to detect if headers are sent

in case junk is being echoed
base height on pixels, not rows
View_DropButton: fixes

Fix DropButton. Some issues showed up when you upgraded this to use View_Popover instead of Flyout. Now it works nicely.

Example usage:
$this->add('View_DropButton', null, 'User_Menu')
  ->setHTML('<strong>Welcome</strong>, '.$this->auth->model['name'])
  ->useMenu()
    ->addMenuItem('#',      'Messages')
    ->addMenuItem('#',      'Settings')
    ->addMenuItem('logout', 'Sign Out')
  ;
Merge pull request #355 from DarkSide666/patch-1

View_DropButton: fixes
Merge branch 'master' of github.com:atk4/atk4
menu js doesn`t block document