Wanhao i3 tool holder extended

Credit for original tool holder goes to realrenshai (https://www.thingiverse.com/thing:2130569).

I wanted larger buckets and multiple buckets. So I used realrenshai's design as a template and rebuilt the holder and bucket in Fusion 360.

I have included the following:

- STL file for holder that accepts two buckets (sharp edges)
- STL file for holder that accepts two buckets (rounded edges)
- STL file for tall bucket
- STL file for short bucket
- Fusion 360 f3d file with all parts. Yo