Gridfinity 4x2 base (snap) optimized for A1 mini

This is 4 sections of 4x2 gridfinity base plate, nested and modified for snap connectors. This is a remix of @PotHix 4x4 plate; his is based on the work by @fldrmaus, which combines the nesting capabilities (printing multiple bases at a time) of @ChillChamp's original model with the snap connectors added by @Neel's remix.