Added Neil Salter's osgUtx library into the distribution, have put all the

orignal seperate headers and source into include/osg/UnitTestFrameWork
and src/osg/UnitTestFramework.cpp respectively.  I have done this to
keep the include and source directories focused on the scene graph rather
than the test framework.

Have added a very simple unit test to Vec3.cpp, which are optionally
compiled in with the OSG_COMPILE_UNIT_TESTS define, which is only
currently defined in debug builds under unix.  It should be fine to
add it in under Windows project files as well.

Finally, a new demo app osgunittests runs the tests and reports success
or failure of the tests.

VisualStudio/VisualStudio.dsw

@@ -279,6 +279,27 @@ Package=<4>
 
 ###############################################################################
 
+Project: "Demo osgconv"=.\Demos\osgunittests\osgunittests.dsp - Package Owner=<4>
+
+Package=<5>
+{{{
+}}}
+
+Package=<4>
+{{{
+    Begin Project Dependency
+    Project_Dep_Name Core osg
+    End Project Dependency
+    Begin Project Dependency
+    Project_Dep_Name Core osgDB
+    End Project Dependency
+    Begin Project Dependency
+    Project_Dep_Name Core osgUtil
+    End Project Dependency
+}}}
+
+###############################################################################
+
 Project: "Demo osgcopy"=.\Demos\osgcopy\osgcopy.dsp - Package Owner=<4>
 
 Package=<5>