Parametric DuPont Shell

I was running out of dupont single "shell". So I decided to print my own.

Might also be fun to print in different colors, for color coding. Either match the wire color, or use some other color coding like different colors for all input, output, power, etc.

I increased the spaces around the locking tab to account for the increased first layer width.

I did not really need other "sizes" except for singles, but decided to make it customizable, so it is easy to print (1-5) other sizes.