Add minimalistic note about using helpers
Add minimalistic note about using helpers

This is probably not enough, but I think it's at least worth mentioning it. see https://github.com/straydogstudio/axlsx_rails/issues/19
straydogstudio/axlsx_rails,straydogstudio/axlsx_rails,straydogstudio/axlsx_rails,straydogstudio/axlsx_rails