[TYPO3-core] RFC: Move the BE logo generation code into a separate method so it can be used from other classes

[Ingo Renner]

more notes:
* also see http://bugs.typo3.org/view.php?id=6522


* example of how to include only the class in alt_toplogo.php after the 
change:

$GLOBALS['includeClassOnly'] = true;
require_once ('alt_toplogo.php');
$GLOBALS['includeClassOnly'] = false;


* we could also move that includeClassOnly stuuf into a t3lib method I 
guess..

That method would then take care of setting and unsetting the global 
variable.


Ingo