generate error from CLI when a file in conf does not exist

[Mearman]

produce some output when the cli tries to load a file from the conf that does not exist. perhaps have a flag that causes is a hard fail.

[combolek]

Are you sure it doesn't already? When I have a non-existent file in plater.conf I get this error when trying to run from the command line:

$ plater plater.conf
* Reading from plater.conf
! Can't process: Can't open file foo.stl for reading

and no plate_001.stl is created.