Could we support ARM64

It would be nice to use the 64-bit OS, either in addition to, or instead of, the 32-bit version. I have not investigated this.

Advantages of using ARM64:

• you'd get to use all the RAM if you have >8Gb
• presumably it's faster in places.

Disadvantages of ARM64:

• you can't run it on Raspberry Pi 1 or 2. I believe Pi 3 was already 64-bit.
• piwheels does not support ARM64

I think the number of people using Pi <3 is vanishingly small. We don't officially support or test that configuration. If anyone pops up on the forum needing a 32 bit OS, it's possible to generate one.

I'm tempted to say, this is an easy switch if we can install everything we need on the 64 bit version.