TimeSeries Support

[sfalkena]

Updating samplers by:

• Pre-calculating all chips for all samplers, now we can also save the chips of random sampler for inspection.
• Moving utilities such as filtering, worker split to GeoSampler, so that every sampler can use this.
• Adding return_as_sits to GeoDataset, so every dataset supports this attribute.
• Set return_as_sits for IntersectionDataset and UnionDataset.
• Fix tests that are failing now
• Add tests for added functionality

Todo:

• Add train_val split function to GeoSampler

[borobaya]

LGTM!

[stypoumic]

Body of the function missing or is this simply a placeholder?

[sfalkena]

It is an abstract method, so all classes implementing GeoSampler should define a function called get_chips. Python automatically raises an error if your class does not have a get_chips function