Modular stackable alligator clip holder

This is a WIP for a modular alligator paint stick holder. These are stackable and can be joined together to secure them. Base model is 50mm x 100mm and sized for standard 3mm and 4mm skewers.

Edit 1: Modifications based on feed back

• Narrowed base slightly to allow better vertical stacking.
• Added small, medium, and large versions.
• Removed unneeded locks.
• Added a channel to make clearing support from the lock area easier.
• Added a quarter sized test version to print for checking fits.

Edit 2: Modifications for print time and fit

• Added a solid bottom for the first few mm to improve print time and adhesion on the larger models.
• Slightly widened the keyhole to apply less stress on the large model's double lock.