Nice little things

[felimomo]

Now the train script has an id argument (to avoid having to go into the hyperpars/yaml files to change id every time one runs a new training run).

New syntax:

python path/to/train.py -f path/to/hyperpars-config/file.yml -pb <True/False> -id <StringId>

@nicolalove I put you as a reviewer to check this out! (It'll be on the main branch, let's merge it to your branch soon to get that convenience!)