added cppunit unit testing framework, using cmake, stripped out the original build systems.

added starting point for Bullet unit tests, with one example unit test
Enable the option BUILD_UNIT_TESTS in cmake to build the test. Note that the test doesn't automatically run.

UnitTests/cppunit/include/cppunit/Outputter.h

@@ -0,0 +1,26 @@
+#ifndef CPPUNIT_OUTPUTTER_H
+#define CPPUNIT_OUTPUTTER_H
+
+#include <cppunit/Portability.h>
+
+
+CPPUNIT_NS_BEGIN
+
+
+/*! \brief Abstract outputter to print test result summary.
+ * \ingroup WritingTestResult
+ */
+class CPPUNIT_API Outputter
+{
+public:
+  /// Destructor.
+  virtual ~Outputter() {}
+
+  virtual void write() =0;
+};
+
+
+CPPUNIT_NS_END
+
+
+#endif  // CPPUNIT_OUTPUTTER_H