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.

src/osg/Vec3.cpp

@@ -0,0 +1,70 @@
+// Vec3 is implemented entirely in the header. This .cpp file just
+// contains utx test code
+
+#ifdef OSG_COMPILE_UNIT_TESTS
+
+#include <osg/Vec3>
+#include <osg/UnitTestFramework>
+
+#include <sstream>
+
+namespace osg
+{
+
+class Vec3TestFixture
+{
+public:
+
+	Vec3TestFixture();
+
+	void testAddition(const osgUtx::TestContext& ctx);
+	void testSubtraction(const osgUtx::TestContext& ctx);
+	void testScalarMultiplication(const osgUtx::TestContext& ctx);
+	void testDotProduct(const osgUtx::TestContext& ctx);
+
+private:
+
+	// Some convenience variables for use in the tests
+	Vec3 v1_, v2_, v3_;
+
+};
+
+Vec3TestFixture::Vec3TestFixture():
+	v1_(1.0f, 1.0f, 1.0f),
+	v2_(2.0f, 2.0f, 2.0f),
+	v3_(3.0f, 3.0f, 3.0f)
+{
+}
+
+void Vec3TestFixture::testAddition(const osgUtx::TestContext&)
+{
+	OSGUTX_TEST_F( v1_ + v2_ == v3_ )
+}
+
+void Vec3TestFixture::testSubtraction(const osgUtx::TestContext&)
+{
+	OSGUTX_TEST_F( v3_ - v1_ == v2_ )
+}
+
+void Vec3TestFixture::testScalarMultiplication(const osgUtx::TestContext&)
+{
+	OSGUTX_TEST_F( v1_ * 3 == v3_ )
+}
+
+void Vec3TestFixture::testDotProduct(const osgUtx::TestContext&)
+{
+	
+}
+
+OSGUTX_BEGIN_TESTSUITE(Vec3)
+	OSGUTX_ADD_TESTCASE(Vec3TestFixture, testAddition)
+	OSGUTX_ADD_TESTCASE(Vec3TestFixture, testSubtraction)
+	OSGUTX_ADD_TESTCASE(Vec3TestFixture, testScalarMultiplication)
+	OSGUTX_ADD_TESTCASE(Vec3TestFixture, testDotProduct)
+OSGUTX_END_TESTSUITE
+
+OSGUTX_AUTOREGISTER_TESTSUITE_AT(Vec3, root.osg)
+
+}
+
+#endif