#50 enable export of timezone from metadata in to-mos

[FWuellhorst]

This closes #50.

Todos:

• Check correctnes
• Add test
• add epw output and possibly others

[MartinRaetz]

Thank you very much @FWuellhorst.

Can you confirm that the tests will cover sufficiently the new feature? Since its the new default the regression tests should be running on the new default.

[FWuellhorst]

@MartinRaetz: I checked locally in Dymola for a single test and the feature works well for Modelica.

@TobiasSpratte : Can you check the with E+ if the exported .epw with the timezone also works as expected, especially in combination with SPAWN and mos. I don't know how to access the weather results from E+ in Spawn.

Future development options:

• Add a simple test model to at least check created mos files locally for different tilts and orientations, see screenshot

• Make all tests check both utc and export with timezone
• add an example with a different timezone (e.g. -6) to trigger edge cases for large shifting

What do you think @MartinRaetz ? I would do that in other issues to keep this one focused on the timezone aspect.

[TobiasSpratte]

I have checked the exported .mos and .epw files in EnergyPlus, Spawn and Modelica and everything works as expected. Thank you @FWuellhorst !

[MartinRaetz]

Thank you for this major PR! I think its a very helpful modification to meet the users expectations!

[FWuellhorst]

@MartinRaetz @TobiasSpratte
I added regression tests which simulate the generated time-shifted mos in Modelica on different tilts and directions. You can create these and more plots with the new test_mos_simulation, executed as a plain python script locally.

Tilted roof first day of year diffuse radiation

Tilted roof in summer direct radiation

Overall, when exporting time zones shifts are valid. Shifting larger than 6-8 hours compared to the imported data, the values become higher in the plot, which is caused by the values of the next day in the original data.
Still, I stored the _imported_timezone (which is set in the import classes with "set_imported_timezone" and added a warning if someone changes the default timezone of the import.