Improve get_dmi_climate_data function

[AdamRJensen]

• Check if the monthly/yearly data is the start or end of the period
• Investigate issue with timestamps when requesting all parameters when frequency is not hourly
• Extend function to also support gridded dataset (either based on latitude/longitude or grid cell)
• Make _fetch_station_meta a public function (return more fields)
• Improve error message (raise_for_status() doesn't return the descriptive errror messsage)

Grid: https://dmidk.github.io/Climate-Data-Grid-Map/