Motivated by [#147](https://github.com/kennetek/gridfinity-rebuilt-openscad/issues/147), I think it ends up more intuitive if upon opening the bin is actually a bin.
From a first impression perspective, it seems unlikely a user is opening up the bins.scad to produce a bin-sized-blank vs. a bin.
Scoop parameter can now be any real number. Follows the same logic as before, where false (now 0) means no scoop, and true (now 1) means regular scoop. Any real number will scale the scoop value to preference.
Changed `enable_lip` to `style_lip` to allow a choice between a regular lip, removal of the lip (losing 3.6mm of height) or remove lip while retaining the regular height
- renamed a bunch of stuff to make people's lives hard ig (more because the file hierarchy was really bad and needed improvement to make other dependent modules)
- updated README documentation to match new modules
- new constants file to clear up clutter in main files
- base function now separate from the bin function