Seasonal greenhouse growth

Greenhouses only produce during each crop's realistic growing months. Active ONLY when "Seasonal Growth" is enabled in the game - otherwise everything works as usual.

HOW IT WORKS
- Each crop has a saved "wish" (should produce: yes/no). It only actually produces when the wish is ON AND the crop is currently in season.
- Outside the season, input intake and output of that good are blocked.
- Only lines you start yourself are affected.

CONTROLS IN THE PRODUCTION MENU
- During the season: the normal "Activate/Deactivate" button controls production directly.
- Outside the season: instead you get the "Mark for season" / "Remove seasonal wish" button (default key X) to set or clear the wish at any time.

SEASON PER CROP
- Strawberry: April-July
- Lettuce: March-October
- Tomato: May-October
- Spring onion: March-October
- Napa cabbage: March-May & September-November
- Chili: May-October
- Garlic: October-July
- Enoki/Oyster mushroom: all year

Multiplayer supported