Bigger/longer solder pads on shield v1.5

[t0mpr1c3]

Jonathan and Viktoria raised a point on the Discord about the solder pads on the shield. Version 1.4 has mostly large, elongated pads which are easy for inexperienced users with cheap soldering irons to assemble. Version 1.5 should keep these long solder pads where possible. LEDs and resistors will have smaller pads, but it should be possible to switch from circular pads to those with an elongated or octagonal shape.

[VIPQualityPost]

Do you want to roll this in on your open PR or do you want me to do it after it gets merged?

[t0mpr1c3]

Let's do it after the merge. There will probably be other changes too.