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- switch to ContextManager for COG and STAC (rio_cogeo.io.COGReader, rio_cogeo.io.STACReader).
- COGReader.part and STACReader.part return data in BBOX CRS by default.
- STACReader now accept URL (https, s3).
- add more method for STAC (prewiew/point/part/info/stats).
- add expression for COG/STAC preview/point/part.
- add `masked` option in `rio_tiler.reader.point` to control weither or not it should return None or a value.
- remove mission specific tilers (195).
- remove `rio_tiler.reader.multi_*` functions (replaced by rio_tiler.io.cogeo.multi_*).
- remove `rio_tiler.utils.expression` (replaced by expression options in tilers).