Breaking changes

Full changelog available in Release history.

3.0.0b3

:meth:`~eodag.api.core.EODataAccessGateway.download` / :class:`~eodag.types.download_args.DownloadConf` parameters outputs_prefix and outputs_extension renamed to output_dir and output_extension.

:meth:`~eodag.api.core.EODataAccessGateway.search` method now returns only a :class:`~eodag.api.search_result.SearchResult` instead of a 2 values tuple. It can optionally store the estimated total number of products in SearchResult.number_matched if the method is called with count=True (False by default).
- eodag < 3.0.0b1 syntax:
```
search_results, number_matched = dag.search(productType="S2_MSI_L1C")
```
  Traceback (most recent call last):
  
  File "<stdin>", line 1, in <module>
  
  ValueError: too many values to unpack (expected 2)
- eodag >= 3.0.0b1 syntax:
```
search_results = dag.search(productType="S2_MSI_L1C")
```
Packaging refactoring and new optional dependencies. EODAG default installs with a minimal set of dependencies. New sets of extra requirements are: eodag[all], eodag[all-providers], eodag[ecmwf], eodag[usgs], eodag[csw], eodag[server], eodag[stubs]. Previous existing sets of extra requirements are also kept: eodag[notebook], eodag[tutorials], eodag[dev], eodag[docs].
```
# install eodag with all available providers supported
pip install "eodag[all-providers]"
```

Adds product type search functionality
The cli arguments are now fully compliant with opensearch geo(bbox)/time extensions