Re-write interfaces pages

[Gadgetoid]

The interface pages badly need an overhaul, they've broadly had the same text since they were originally created and it tends to waffle about devices I was playing with at the time, and include vague code snippets that are maybe out of scope for pinout.

Rough TODO:

• [ ] Drop code snippets, we're a pin documentation website, let's stay in our lane
• [ ] Remove references to wiringPi on pages (but don't remove wiringPi page), while it's on life-support it's still officially deprecated
• [ ] Avoid waffle about devices/arduinos, eg: https://pinout.xyz/pinout/spi
• [ ] Document related dtoverlays/config/methods of enabling
• [ ] Find some useful text for JTAG (see #321)
• [x] Update 5v power text- does this still apply? Don't be too chatty
• [x] Update 3v3, current limits Pi 4, Pi Zero W etc? Maybe a breakdown/table
• [ ] 1-Wire page is very hard to read, all the code snippets are low contrast
• [x] Add a PWM page?

Additionally the home page has been overloaded with a lot of things, and is starting to look very, very busy:

• [ ] Drop orientation text, as it's in the legend now
• [ ] Drop "Explore HATs & pHATs" and re-word the link at the top of the page to better describe the section: "Explore pinouts for HATs, pHATs & more" maybe
• [x] Move the pHAT Stack link somewhere in the UI and maybe casually drop it into the intro text like the boards page
• [x] Improve intro text, "designed to be" is non-comittal and redundant, it "is".
• [x] Make sponsor links 100pt comic sans ms in red, and surround with blink and marquee tags
• [ ] Drop Rogue from "Maintained by", replace with @lurch ?

[Gadgetoid]

@lurch before I add you into the Pinout footer:

1. Do you want to be credited there?
2. Do you have a preferred link? I was just going to use GitHub profile