[Cdash] Uploading to CDash fails most of the time

[Mathias Gaunard]

I have XML files generated from CTest to send to the CDash server. The
files are about 5MB each, and uploading fails most of the time.

I don't know if this is a CTest or CDash issue, but it prevents me from
using CDash.
I could find documentation about using alternative methods (FTP, SCP),
but the documentation is for Dart, not CDash.

I don't know if it would be possible to compress the XML files either,
which would significantly reduce the required bandwidth.