Windows: ship QtSql lib

cmake/modules/NSIS.template.in

@@ -318,6 +318,7 @@ Section "${APPLICATION_NAME}" SEC_APPLICATION
    File "${QT_DLL_PATH}\QtCore4.dll"
    File "${QT_DLL_PATH}\QtGui4.dll"
    File "${QT_DLL_PATH}\QtNetwork4.dll"
+   File "${QT_DLL_PATH}\QtSql4.dll"
    File "${QT_DLL_PATH}\QtXml4.dll"
    File "${QT_DLL_PATH}\QtWebKit4.dll"