Add wxOVERRIDE to test files

And cleanup some tailing spaces and tabs.

tests/controls/spinctrldbltest.cpp

@@ -25,8 +25,8 @@ class SpinCtrlDoubleTestCase : public CppUnit::TestCase
 public:
     SpinCtrlDoubleTestCase() { }
 
-    void setUp();
-    void tearDown();
+    void setUp() wxOVERRIDE;
+    void tearDown() wxOVERRIDE;
 
 private:
     CPPUNIT_TEST_SUITE( SpinCtrlDoubleTestCase );