Add more options to select patches for training

[danifranco]

The idea is to have more options apart from DATA.TRAIN.MINIMUM_FOREGROUND_PER. Intensity based measurements seem to be useful for users, e.g. mean, min/max, std (see forum.sc thread).

[pr4deepr]

Just to add, this would be very useful for inference as well..

[danifranco]

Hello @pr4deepr !

We have implemented the filtering for training/validation and test (ad6329716457f7d860eb8dc4964109b6f9e7e394). You can use it with DATA.*.FILTER_SAMPLES variables (e.g. train variables here). Hope you like it!

I'm closing this but feel free to create a new issue if you have any problem.