Remove harvester dependency on RenderUnit.
Add WithHarvestAnimation for TS and D2K harvester animations.
Allow Harvester to define the number of harvestable facings.
Add D2k harvest animation.

harvest2.shp is movingsand2.shp with a corrected frame order.
Fix D2k harvester dock animation.
Merge pull request #3458 from pchote/harvester-animations

Fix the harvest animations for TS and D2k.