Chemisty quality-of-life changes

These changes aim to make it easier to load the medical fridge as a chemist/CMO.

Changes:

- Medical belt now able to pick up multiple items if used on medical item (similar to plastic bag/plant bag/ore bag etc)

- Medical belt, if used on the medical fridge, will unload items into the fridge.

- Pill bottle, if pulled onto the fridge, will now empty its content into the fridge.

Forum discussion thread: http://80.244.78.90/phpBB3/viewtopic.php?f=12&t=2232