Fix config and prediction revamp. (#259)

Extend single_test_optimization.py to be able to use real world data from new prediction classes.
- .venv/bin/python single_test_optimization.py --real_world --verbose
Can also be run with profiling "--profile".

Add single_test_prediction.py to fetch predictions from remote prediction providers
- .venv/bin/python single_test_prediction.py --verbose --provider-id PVForecastAkkudoktor | more
- .venv/bin/python single_test_prediction.py --verbose --provider-id LoadAkkudoktor | more
- .venv/bin/python single_test_prediction.py --verbose --provider-id ElecPriceAkkudoktor | more
- .venv/bin/python single_test_prediction.py --verbose --provider-id BrightSky | more
- .venv/bin/python single_test_prediction.py --verbose --provider-id ClearOutside | more
Can also be run with profiling "--profile".

single_test_optimization.py is an example on how to retrieve prediction data for optimization and
use it to set up the optimization parameters.

Changes:
- load: Only one load provider at a time (vs. 5 before)

Bug fixes:
- prediction: only use providers that are enabled to retrieve or set data.
- prediction: fix pre pendulum format strings
- dataabc: Prevent error when resampling data with no datasets.

Signed-off-by: Bobby Noelte <b0661n0e17e@gmail.com>

src/akkudoktoreos/prediction/weatherbrightsky.py

@@ -96,8 +96,8 @@ class WeatherBrightSky(WeatherProvider):
             ValueError: If the API response does not include expected `weather` data.
         """
         source = "https://api.brightsky.dev"
-        date = to_datetime(self.start_datetime, as_string="%Y-%m-%d")
-        last_date = to_datetime(self.end_datetime, as_string="%Y-%m-%d")
+        date = to_datetime(self.start_datetime, as_string="Y-M-D")
+        last_date = to_datetime(self.end_datetime, as_string="Y-M-D")
         response = requests.get(
             f"{source}/weather?lat={self.config.latitude}&lon={self.config.longitude}&date={date}&last_date={last_date}&tz={self.config.timezone}"
         )