Version 0.4.2

Change log:

• Added tqdm progress bar to EOExecutor.
• Switched from multiprocessing to concurrent.futures in EOExecutor.
• ExportToTiff can now export multi-channel tiff images and works with time-dependet features. Contributed by @wouellette
• Updated package to support sentinelhub-py version 2.5.0.
• Fixed value overflow bug in InterpolationTask (could happend only on Windows machines).
• Fixed problem with time interval parsing in eolearn.io.
• Improvements in EOWorkflow, added get_tasks method.
• Added instructions for contributions and code of conduct.