Fix typo in ctkExampleDicomHostPlugin

Plugin name should be org_commontk_dah_examplehost
instead of org_commontk_dah_examplehost_Export_Export

Plugins/org.commontk.dah.examplehost/ctkExampleDicomHostPlugin.cpp

@@ -56,6 +56,6 @@ ctkPluginContext* ctkExampleDicomHostPlugin::getPluginContext() const
   return context;
 }
 
-Q_EXPORT_PLUGIN2(org_commontk_dah_examplehost_Export_Export, ctkExampleDicomHostPlugin)
+Q_EXPORT_PLUGIN2(org_commontk_dah_examplehost, ctkExampleDicomHostPlugin)