Support models that predict continuous-valued outputs #59
Description
PR #58 allows users to use the selene_sdk.samplers.file_samplers.MatFileSampler for models that predict on continuous-valued outputs (e.g. regression models).
Before this PR, the MatFileSampler only supported integer labels, and all other samplers only support binary labels. We would like to modify more of the existing samplers (and/or create new samplers) in Selene that can support continuous-valued labels.