memory manager published at flipcode.com. This can be turned on
with the OSG_USE_MEMORY_MANGER option which then uses custom global
new and delete operators as well as provide osgNew and osgDelete macro's
which add ability to log line and file from which calls are made.
Updated osg,osgUtil,osgDB,osgText and osgPlugins/osg to use osgNew/osgDelete,
and fixed memory leaks highlighted by the new memory manager.
change in osg::Billboard.
Removed in instance of an object being passed () brackets, have removed the
brackets to avoid an amiguity with the compiler intepreting it as a function.
