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.
Also move osg across to using radians for angular paramters by default.
By defining USE_DEGREES_INTERNALLY you can get the OSG to revert to
the old style degrees. This later feature is deprecated and only meant
for helping comptability in the interim.