Update tests to sites.ecmwf.int (#77)

* Update tests to sites.ecmwf.int, disable some google tests due to index ranges

Add warning to readme (#75)

* Add warning to readme

* Add warning message when using source=ecmwf

Fix formatting

Add attribution message after download (#72)

* Add attribution message after download

* Bump version

Bump version

If model in retrieve use it instead of model from client (#69)

* If model in retrieve use it instead of model from client

* Do not overwrite client state for model when model is in retireve but only use that value for that retireve

* Update readme and examples removing reference to test-data for aifs-ens

Add coercion for aifs-ens to correctly generate urls (#66)

* Add coercion for aifs-ens to correctly generate urls

* Add tests for aifs-ens requests

* Update readme and version number

* Add example to readme using aifs-ens

* Fix broken link to file naming convention

* Add examples dir with earthkit example than retrieves aifs-ens data via opendata and then plots the data

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Co-authored-by: awarde96 <[email protected]>

Merge pull request #63 from ecmwf/floriankrb-patch-4

Update __init__.py to 0.3.19 version number

Update version to 0.3.18

Update version number to 0.3.17

Update __init__.py version number to 0.3.17