-changed sampling from daily to monthly
-fixed Metadata.construct parameter order

toar_rest_client: DownloadAnalysisService:
-added CF name of variable to sample file name

fixed typos and added some documentation

In dataclass attributes with an explicit setter to restrict the valid parameters are treated as having a default value by python

changed constructor of MetaData

now new notebook for obtaining sample data is running
added old version as example how a request can be generated manual

worked on documentation of code

started documentation as example

fixed some typos.

added comments to produce_data example

- fixed bug in plotting of station positions

README.md
- started rework of documentation of examples

.gitignore added directory used for examples

made adoptions to the updates by Simon

- added creation of subdiretories
- added some output