KiCad-Nightly currently not supported → tell user if he tries!

Start Page and with new revision:
currently if you upload a KiCad-Nightly board file it just displays Import failed, please contact our support
would be super nice to just include a very short check on the file if it is a supported version.
and if not tell the user to use KiCad stable OR use the Push-To-Aisler plugin (that works with KiCad nightly)

Thanks for the input, I think that could definitely help!