CUBE POT MOLD remix

Changed a few things:

- got rid of the clips and just put on flat flaps to use binder clips
- got rid of the pokey top inner part because they didn't even line up; replaced with two pokey things and slots, to better align the inner part
- added little markers on the inside of the outer parts as a guide for fill level before inserting inner part (fill mortar upto the line, then insert the inner part - it should be close)

Tips:
- you'll need supports for the inner part, and it might be a bit tricky to remove so use tree structure
- fill the inner part with sand or rocks to keep it from floating up after pouring the concrete