Add support for files from matrix builds

This is probably not the best way to do this, but the idea is to use parameter file that come from a specific axis of a matrix build and not from the master.

If no specific axis is specified we prefer the master. If the file does not exists there, we go look for it in slave and pick the first one.
If a specific axis is required, match the first node with this parameters where the file exists.

Signed-off-by: Nicolas Morey-Chaisemartin <nmorey@kalray.eu>