Add wxUSE_ARTPROVIDER_STD build option.

Make it possible to exclude wxDefaultArtProvider from build. Now that a
Tango-based provider exists, it may make sense to disable the standard bitmaps
if the program doesn't need the few of them not provided by Tango anyhow.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66506 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/artprov.cpp

@@ -440,7 +440,9 @@ class wxArtProviderModule: public wxModule
 public:
     bool OnInit()
     {
+#if wxUSE_ARTPROVIDER_STD
         wxArtProvider::InitStdProvider();
+#endif // wxUSE_ARTPROVIDER_STD
 #if wxUSE_ARTPROVIDER_TANGO
         wxArtProvider::InitTangoProvider();
 #endif // wxUSE_ARTPROVIDER_TANGO