Meteoblue-dataset-sdk

Support to cache temporary results on disk. The cache implementation is generic. A new cache can be provided that implements the [cache abstract base class](https://github.com/meteoblue/python-dataset-sdk/blob/master/meteoblue_dataset_sdk/caching/abstractcache.py).

python
import zlib
from meteoblue_dataset_sdk.caching import FileCache
cache = FileCache(path="/tmp/my_cache_dir", max_age=4000, compression_level=zlib.Z_BEST_SPEED)
client = meteoblue_dataset_sdk.Client(apikey="xxxxxx", cache=cache)

Fixes:
- Add workaround to use `querySync` in jupyter notebooks
- Update protobuf definition to include solar PV calculation parameter

This library now declares a stable interface with version 1!

Time intervals are now encoded more efficiently

This is the first working version that can now be used to gather initial feedback.